User interface: The 5% that's really 100%

We have a saying in our office, which is that the interface is only 5% of what we do but 100% of what the user sees. To be more accurate, it's usually me who says it, typically to a background chorus of grinding teeth. This is not to say that the rest of the team don't care about the user experience, but when, for example, you've just coded a complex administration function to enable to a client to set up their own algorithms for customer discounts, you're probably expecting a bit of praise and congratulation, and not someone scratching his head and asking whether the submit button shouldn't be a bit further up the screen. (There's a lesson for me, there.)

However, there are two very good reasons for thinking about the user and the interface that they will use.

Firstly, if you've built a system, then you want people to use it and there are four key components to giving them an experience they will be happy to repeat.

1. Visual appeal: People make very rapid, non-intellectual decisions about websites that they are presented with. If the screen is cluttered or badly rendered, the user is already less inclined to engage with it. Screen design is hugely important; it makes the system look like it will work.

2. Guidance: if your user has to study your screen to work out where to start, then you've already failed. It should be clear to the user what they need to do first or what their options are. Positioning the cursor for them, big, clearly labelled buttons, numbering steps: these all go a long way to giving the user the 'no brainer' experience that they want. And a little onscreen text is a simple, cheap way to help the user to understand what's required of them and what's going on.

3. Feedback. Our local tourism board has a purchasing system that it allows some attractions to use. Booking tickets for a show, I selected the number I wanted and clicked add to basket. Nothing happened so I tried again, twice more. Still nothing. So I went to the checkout only to find I had enough tickets in my basket to take most of the people living on my street to the theatre with me. I think the message here is clear; when the user completes an action, let them know it's done!

4. Deference. With software, you can, of course, force users into doing things by preventing them from proceeding if they don't do what they're told. However, this may not give you the results you want. It's all very well collecting, for example, marketing information from your users but if you force them to enter a date of birth, you may find they enter something completely random, thereby skewing your data. In a similar vein, an e-commerce site lost my business this week when they deemed my nine-character-with-a-numeric password to be not strong enough for their standards. Don't throw your weight around: give your users what they want and need, and if you want something from them, ask don't demand.

Secondly, there is a very selfish reason for helping your user to have a good experience with the software you build; fewer support calls. If people need to use the software - let's say it's for a timesheeting system - then if they can't do what they need to do, they're going to call. And, people being people, they probably won't read lengthy help text or instruction guides: they'll give up or pick up the 'phone. One way or another, that will come back to the software provider.

Usability, particularly the second point, can be tested easily during your User Acceptance Testing (UAT). The client knows what they want the system to do, the software provider has built that system. Leaving the client to test the system without initial guidance from the provider puts the client in the same shoes as the user. If the client can't get from A to B or product to checkout without guidance from the software provider, what chance has the user got, when they come to the website or software completely cold?

Usability is about empathy, putting yourself in the user's shoes: put the little bit of effort into giving them some guidance through your design and text, and you'll have happy users and a quiet help desk.