UI Design Principles from Mozilla Labs

labslogoAs part of the Labs concept series, I attended an online talk by Alex Faaborg from Mozilla UX, presenting Jakob Nielsen’s 10 principles for software usability design. They are simple and useful, so here they are.

  • Keep system status visible: Is there a web page loading right now? Am I in private browsing mode? The user should be kept aware of the current status, and feeback on modes should be timely. When a user doesn’t know which mode we’re in, this is called a mode error.
  • Systems should mirror the real world: Engineers want to implement whatever the technology makes easy to implement – but users want to use something that mirrors the world as they see it. Some technology elements are still confusing (e.g. Fx asking if you want to resend POSTDATA) but some are now commonplace (404 errors or the http:// prefix). Real world elements can appear in icons (padlocks, floppy drives, gold stars) or replicating a real life method (e.g. having a desktop).
  • User control & freedom: Don’t prevent users from doing certain things. For example, in Fx3 it’s impossible to bring back the Most Visited folder on the Firefox bookmarks toolbar if you delete it.
  • Consistency & standards: Be consistent internally with the way you’re always represented things inside your application, and be consistent externally with the wider OS or peer applications. These could conflict – Fx changed the bookmarks icon in v3 from a bookmark to a gold (or blue) star to fit with other browsers.
  • Recognition not recall: The command line requires you to remember everything, which is why most users find it too tough to use. Ubiquity suffers from this in a way – although it does a lot to help you, it can’t do anything unless you type something.
  • Flexibility & user efficiency: Toolbars that are malleable are flexible, but it’s tough to create complete flexibility, as very flexible UI systems (like Ubiquity) require some skill to use completely.
  • Minimalist design: Visual clarity is good. Reduce redundant elements (e.g. the address bar URL, the window title and the tab title). Combine elements logically – the iPod wheel combines a set of functions into one element while keeping it easy to use.
  • Error prevention: fix common user errors like commas in URLs.
  • Help users recover from errors: proactively provide contextual help, like the internet connection wizard in Safari.
  • Help and documentation: ensure users know where it is and can access it.

Balancing things out

The keen ones amongst you will have spotted that not all of these things are achievable – balances are needed between these elements, and the correct position depends on the user and the application. Here are the contradictions – and the balances – that I can identify.

  • More user control and freedom can mean less minimalism, less error prevention and less consistency. The user can reconfigure away from standards.
  • More recognition can mean less minimalism. The command line is an awesome interface for the right kinds of people.
  • More system statuses can mean less minimalism. Where do you put the throbber in a chromeless browser?

Creating an awesome design – it seems – is about finding ways of winning on both sides of these balances so that compromise becomes less necessary. At the same time, we must recognise that no system is going to be perfect for everyone – as the market becomes more diverse, the interface must understand and trade off different requirements in that market.

Lawrence Lessig at the Kellogg School of Management

This week I was delighted to have the opportunity to hear Lawrence Lessig – all-round free culture badass – speak at Kellogg, and was not disappointed.

Lawrence has shifted his focus away from IP law and policy, and towards fixing broken government. This was, I admit, a slight disappointment – it makes sense to try and attack the root cause of an issue, but Lessig may be biting off more than he can chew.

His talk was a master class in presentation, and he presents a series of very well constructed arguments, but always with a diplomacy that suggests he is already well ingrained in the political process.

The presentation he gave was a longer version of this one:

Still – I like plain logic, so here’s a breakdown of his argument. This is a travesty actually – the presentation was so well done that this is like reading the ingredients on a wedding cake.

Note: I’m afraid that I missed some of the details here, so apologies for the crappy blankets statements like “x has doubled”.

The Basic Problem

Lessig’s basic argument – money creates mistrust, so campaign contributions are a dumb idea. Money doesn’t make people liars, but it makes people suspicious of their motives. Examples:

  • Big pharma companies donating to the AHA to pass Activase. Apparently, even the free pens and coffee mugs change prescribing behaviour.
  • Hilary Clinton voting down “that awful bill” about personal bankruptcy, getting campaign contributions from credit card companies and then switching her vote next time around
  • Sugar industry lobbyists against the WHO’s recommendation of 10% maximum sugar intake
  • A note that no peer reviewed journals disagreed with Al Gore’s basic points on global warming while 53% of the popular media articles in the same time period disagreed
  • A response to Al Gore’s proposed internet telecoms deregulation – “How are we going to raise money from this if we deregulate?”

Then, some notes on the current situation:

  • The number of lobbyists has doubled, and the amount they get paid has doubled – therefore their influence must be rising
  • Representatives spend between 30% and 70% of their time currently raising money

… with the basic problem being that noone has any interest in stopping this problem.

There were a few notes on the history of these sorts of problems, with the point being that in Lessig’s opinion, we have a more moral government than ever before, so we should be more disposed to solve these problems now than ever before.

The Proposed Solution

… is this: have government representatives get money only from private citizen donations, with additional set funding from the treasury once a campaign has reached a certain size.

The main site for this proposal is here. If you’re a politically active American and you like these ideas, it’s worth a peek.

Pricing your Product


Pricing a product (or service) is hard, and there’s no set way of doing it – but there are few things to bear in mind.

Cost Plus Pricing

If it costs you $100 to make a product, it might make sense to price it at, say $120 to give you a $20 margin. This does form a useful floor to pricing – if you determine that it costs more for you to produce something than you can sell it at, then you’re in deep doo-doo. But it’s generally a dumb idea to use this alone for pricing. Here’s why.

Value to the Customer

Let’s say that someone buys your product for $120 and uses it directly to make $1000. Suddenly you realise that you could have charged $900 dollars and they would have bought it. In fact:

Price you can charge = value to customer – pain in the ass of using it

The hard part is quantifying that value and pain in the ass. If you’re selling information, or education, the value a customer will gain depends entirely on how they use it. And whatever your product, their perception of their pain in the ass of using it can be changed wildly by how well they know you, whether you can provide support, whether they’ve done it before, and so on.

If you are selling information, you can try to determine its value by estimating how it might change a decision by your customer.

For example – let’s say your customer wants to make an investment of $1000, but isn’t sure what it will return. They estimate a $1500 return with a 50% likelihood and a $500 return with a 50% likelihood, so their expected return is $1000 invested, and hence they aren’t going to bother investing anything. If your information tells them that it’s all good and it actually is a $1500 return per $1 invested, they can make the investment, and will make $500. Hence, $500 is the value of your information (minus the pain in the ass factor.)

Now – I know that’s awfully academic, but we can make it more solid. Let’s say your customer is a construction company, and they are thinking about starting a project which depends on a government permit. If you can help estimate the likelihood that the permit will be granted, you can change those probabilities, and turn a guess into a well informed decision.

Pricing to Competition

That said, business is way messier than that. It just takes too much time to exhaustively estimate every factor that goes into a decision like this (unless you’re dealing with millions of dollars, in which case it probably is a good idea.) So, as a rule of thumb, you can look at what the competitors are pricing at. If a customer can find an alternative to buying your product that’s cheaper, they’ll take it.

More. This is especially true if your product is a commodity (i.e. all the alternatives look just the same, like salt.) But if you can put something in your product that no-one else can replace – a differentiator – that means that you don’t have to worry as much about pricing to the competition. That differentiator could be habit, brand, a relationship or something else.

Final caveat

With all of this, bear in mind that you should always be looking at things from the perspective of the customer. Coke famously installed temperature sensors in their vending machines so that they could raise the prices of the drinks on hot days. It’s completely logical – there will be more demand on hot days, and the value of a cool drink on a hot day is definitely higher than on a cool day. But it just plain annoyed customers who felt they were being gouged (and they were), so people didn’t buy out of principle.


  • Pricing to cost forms a useful pricing floor.
  • Try to determine what value the customer gains out of your product.
  • If that’s too hard, figure out what their alternatives are.
  • Differentiate your product if you can.
  • Don’t forget to think about the customers.

Finance Glossary for Dummies

Theyre bearer bonds. Theyre bonds.
"They're bearer bonds. They're bonds."
Like technology, finance is an area replete with cool sounding words that no one outside finance understands. The dirty secret – they rarely mean anything complicated. So here’s a simple glossary of terms to help you understand what the hell finance people are talking about.

  • Debt: Money that you owe to someone.
  • Equity: Money that belongs to the owners of the company.
  • Risk: The chance that you’ll make money or not. Risk has value – a risky pound is worth less than a riskless pound. For example – if you bet on a dog winning at the track, you don’t put down the value of what you might win to bet, but a much smaller figure, because winning is risky.
  • Security: A security is an investment of any sort, and it’s a word that’s really just meant to confuse non-finance people. For example, if a bank lends money to a someone for a mortgage, they have made an investment in that person. That investment is a mortgage backed security. See?
  • Amortisation: This just means payments spread over a certain amount of time. For example, if you are paying for a sofa you just bought, you could make one large payment up front, or make smaller payments over time, i.e. amortise the payments.
  • Bond: If you’re a company and you need to borrow money, you can issue a bond. That bond is a promise to pay the bond holder the value that’s on the face of the bond by a certain date.
  • Coupon rate: If you decide to issue a bond, you can either pay back your bond holders at the end of a set time (the bond duration), or you could pay back a percentage of the total every so often (say, every month). That percentage is the coupon rate.
  • Discount rate: If you put money in the bank in year one, you’ll get that money back with interest in year two. This means that a pound today is more valuable than a pound tomorrow. That rate which determines the time value of money – which in this case is the interest rate – is more generally called a discount rate.
  • Stock or Share: If you buy a share, you buy a small part of the company. For small companies, this might mean buying out a founder’s capital investment in part or in total. For a large company, this might be buying a share from an investment market – but essentially both are the same thing.
  • Option: An option is, literally, the option (but not the requirement) to buy a share at a predetermined price. You can exercise this option at a future date, or any any time until that future date (depending on the option type).
  • Future: A future is an obligation (or contract) to buy at a specific price, at a specific future date. Pretty much the same as an option, but this time there is an obligation to buy.
  • Beta: Indicates how well a company does versus the economy. See below!

There are some concepts here that bear a little bit of further explanation.


Let’s say the value of one share of Yahoo is $10 right now, and you buy an option on this at a strike price of $10 which you can exercise in a year. This means that in one year, you can buy a share at the preset strike price ($10) and sell it at whatever the current market rates, or you can choose to just let the option go. So, if the stock price next year is $12 you would exercise your option and make $2, but if the stock price next year is $8 you would choose to let the option go. Of course, if the market believes the price is going to go up, then it will cost you something to buy that option.


I won’t go into a discussion on the CAPM – but sound off in the comments if you want me to change this. Instead, here’s the simple version. Beta indicates how you might expect a company’s returns to vary with respect to the market. If:

  • beta = 1.5, it will return 1.5x the market
  • beta = 1, it follows the market
  • beta = 0.5, it is positive when the market is positive but half as big
  • beta = negative, it is positive when the market is negative

So, you can expect the price of large beta stocks to be up when the market is up, and low or negative stocks to be up when the market is in trouble.

How do you determine the beta? By examining historical share prices. By examining the betas of other similar firms. But best of all, by considering consumer behaviour. For example, a firm that manufactures and packages own-brand economy label food might be a negative beta firm, as more people buy economy brand food when times are tough.

Debt & Equity

Debt and equity are weirdly interchangeable.

Usually, equity holders are the owners of the company, they ultimately call the shots, and profit comes back to them. Debt holders just lend money and get paid back.

But it’s not so simple. If you own one share of GE, you’re not calling any shots. Tax shield effects mean that company profits are going to interest payments for debt holders. And those debt holders might have lent GE so much money that they are calling the shots on what happens with that cash.

There are also these things called hybrid securities which are, literally, a hybrid between debt and equity. Oddly, pure debt and pure equity are both extremes of a scale.

Perception Of Pricing


Evil marketing at its finest:
We all know that price promotions usually give an uptick in sales, but it doesn’t matter whether you’re actually cutting price – it only matters whether customers think you’re cutting price.

Case in point: GM’s “Employee Discount” pricing, launched on 2005, turned out to be hugely successful for the company in driving unit sales. However, it turns out the the average transaction price during this period was higher than usual, because shoppers had to pay sticker price (no haggling) and were unable to get the same rebates as usual. A double win for the company!

Even worse, it turns out that shoppers don’t pay much attention to pricing. Two marketing professors went around shops asking people if they could recall what the price was of the item they’d just put into their basket. Here’s what happened:

  • 21.1% had no idea
  • 31.8% guessed and got it wrong
  • 47.1% got it right

The implication there is that price matters, but perhaps less than marketing think it does. Sure, it’s not conclusive – some people could guess right, some people just have bad memories, there’s some variance depending on the item type and so on.

A subsequent study focuses on coffee only – as a staple food, one expects price sensitivity and hence recall to be higher, but the results appear similar. Score one for our conclusion.

However, if we equate “customers think we’re cutting price” with a promo barker, sticker or similar, then we’d need to do a slightly different study. The follow-on study also states that “price-recall accuracy is significantly related to promotion status of the brand and category purchase frequency of the consumer”. So, we have to take the results with a tiny pinch of salt.

Conclusion? If you’re cutting price to drive sales for a promo, just think carefully about how much you actually need to cut. It may be that creating a convincing perception of promo is more important for driving up volume sales.

Mozilla Labs Concept Series: Pie Assisted Gestures

A few days ago, Mozilla Labs invited students to answer the question: “What would a browser look like if the Web was all there was? No windows, no unnecessary trappings. Just the Web.” I thought I’d take a crack at it myself, even though I’m clearly going to get my ass kicked by the engineering undergrads 🙂

Here’s a video I knocked together, which shows a very rough mockup of the UI. The basic idea is this – to extend pie menus in such a way that they can help train users into using mouse gestures, and remain as a backup for more complex commands.

Mozconcept: Pie Assisted Gestures from Shahid Hussain on Vimeo.

Non-Web Monetisation

This week, I gave a short talk on tech business model basics to the Kellogg High Tech Club. I was following an excellent talk by a colleague on web monetisation, so I focused on non-web monetisation. We weren’t able to snag a video camera, but I did punch up some audio and sync it to the slides.

This presentation was featured on the Slideshare front page on Monday 2nd Feb. Thank you Slideshare editors! 🙂

Management For Engineers

It’s been a little while since I posted, and here’s why – I’ve been starting a new website called Management For Engineers.

I originally started knocking together material for this towards the end of last year. As we progress and get more responsibility, engineers often go into management. At the same time, we have been trained with a set of skills that make us great at dealing with some things, like logic and measures, while not as good at understanding other things like, well, what managers do all day.

I hope that the site will encourage engineers to think more deeply about management, and see it as a fun challenge rather than a pain in the ass.

Best Buy Vending Machines

You may have caught a previous post here on iPod vending machines.

During a trip through LAX, I noticed that these machines are being used by Best Buy to sell a variety of electronics to bored travellers – headphones, flip style camcorders, and of course, iPods.


Personally, I was just curious when I was snapping photos, but as I backed away, one fellow actually went and used it.


As he made his selection, the local security guard looked on, either nervous, or just curious that someone was using the thing.

Is selling consumer electronics in this way actually viable?

Before I answer this question, I’ll relate an event that happened a few hours ago.

On our pilgrimage to the local Ikea today, we aimed our trolley straight for the self-service lanes. There was one employee – an older lady – looking after the six self-service checkouts, so she came and did our checking out for us.

This annoyed us.

Here’s why this happened. The Ikea assistant believed that getting service at a checkout is better than not getting service, and she wanted to help. We, the two customers, did not.

Please get back the the point

I would argue that there’s a generational shift happening. Consider these two scenarios.

  • Generally older folk: go into a Best Buy, a Staples, a Currys or Dixons and chat up the salesperson. They don’t know too much about technology, so they’re more likely to take their advice on what to buy – and that advice will be to buy something in the shop that’s in stock.
  • Generally younger folk: research everything they can about a category online before even thinking about buying it. They might buy online or in a store – they don’t value as much whatever added services might be available in store. In short – they can serve themselves.

So – if a product is strongly price controlled and generally very reliable – like the iPod – these weird looking contraptions will offer an element of convenience. 24 hour service. No one getting in your way. All while offering the same price as everywhere else, instant access to the product, and no delivery fee.

Balance that against the natural caution of getting a 300 dollar product out of a vending machine. As the machines get more popular, this caution might dissipate, and the machines become more viable.

Most new businesses have a chicken and egg problem – this one, it seems, is no exception.