Ok, I've been meaning to post this for a while, so sorry it's late... but I talk a lot about 'experience' and user-centred design, and occasionally, I stumble across someone who doesn't come from my universe and isn't as keenly aware of what some of this means. So here begins, hopefully, a small series of blogs on the basic principles of User-Centred Design (UCD) and user experience generally. The aim is to do each in 500 words or less. Something I'm not very good at, so bear with me. Herewith, UCD 101:
User-centred design (UCD) is an industry-standard term for an approach to the design of a solution that takes a detailed look at the needs of the end users of a solution, and then specifically sets about creating things that satisfies those needs.
Done well and in an organisation that truly 'gets it', this approach will drive not simply how something works, but the overall 'product' the company has to offer. UCD is a very effective innovation framework, as it looks at un-met needs in its customer base and potential customer base. This basic approach has been the key driver of invention since forever, so UCD is a perfect framework to drive everything from product innovation to interaction design.
In order to be effective, UCD can't purely be 'user' design. i.e. it cannot simply be 'what users want'. Take a look at Homer's ideal car below to see how bad this approach can be. 
UCD is about understanding users' wants and needs, coupling that with an understanding of what will drive the commercial business and what the technology is capable of, and then design an appropriate, beautiful and enjoyable experience or product.
It's something often summed up as balancing desire, feasibility and viability. Unless you get all three right, the thing will fail.
- Lose 'desire' and nobody will come to use it. Thereby collapsing any business case you had built on it.
- Lose 'feasiblity' and you may not even be able to build it in the first place.
- Lose 'viability' and it will be too expensive, or hard to maintain and the business needs won't be met.
The best products balance all three very effectively. So a UCD process is actually one that also is business-centred and technology-centred. That's a lot of centres... but the secret is mutual gain.
Usually, unless we create something that somebody wants to do ('Desire') it's going to fail. So usually, the reason we call this user-centred is that unless we have users, nothing else works; but as we said in reality the game is mutual gain. We can give users lots of things they want to do, but where is the business value? When we find overlap between user-benefit and business-benefit, those are the magic moments that will make a system or business successful.
Sometimes a business just has to do something. It might be a regulatory requirement for example. But even this requires attention to the 'desire' element. In this case, the base system comes first. "We need a system to get customers to sign our new terms and conditions". Viability is ticked as it's a 'must do', but now we have to address 'desire'. How do we make people do this? It's best if they want to do it as it will happen faster and they will be happier - but what motivates them?
Finally - UCD should have a success metric of user happiness. User happiness is a user benefit that overlaps with business benefits, but is often left unconsidered. In internal systems it leads to staff loyalty and lowered support costs, in customer-facing systems it generates increased trade and loyalty. But more than that, because loyalty can be generated simply by having the right product at the right price and not letting people down on delivery. That's all good, but you can go further. When you get customers emotionally invested in something, you move from simple loyalty, to advocacy, which is a far more valuable attribute for business. It's 'experience' that generates this emotional attachment...
Words: 576 - Doh!
Thanks to / people to read: Alan Cooper - The Inmates are Running the Asylum; Lou Carbone - Clued In.