80% rule

Pareto’s law is more commonly known as the 80/20 rule. The theory is about the law of distribution and how many things have a similar distribution curve. This means that typically 80% of your results may actually come from only 20% of your efforts!

Pareto’s law can be seen in many situations – not literally 80/20 but certainly the principle that the majority of your results will often come from the minority of your efforts.

So the really smart people are the people who can see (up-front without the benefit of hind-sight) which 20% to focus on. In agile development, we should try to apply the 80/20 rule, seeking to focus on the important 20% of effort that gets the majority of the results.

If the quality of your application isn’t life-threatening, if you have control over the scope, and if speed-to-market is of primary importance, why not seek to deliver the important 80% of your product in just 20% of the time? In fact, in that particular scenario, you could ask why you would ever bother doing the last 20%?

Now that doesn’t mean your product should be fundamentally flawed, a bad user experience, or full of faults. It just means that developing some features, or the richness of some features, is going the extra mile and has a diminishing return that may not be worthwhile.

So does that statement conflict with my other recent post: “done means DONE!”? Not really. Because within each Sprint or iteration, what you do choose to develop does need to be 100% complete within the iteration.

It’s also worth considering the impact on user experience. Google has shown us that users often prefer apps that do just what you want. That’s just what you want. And no more. The rest is arguably clutter and actually interferes with the user experience for only a limited benefit to a limited set of users.

So in an agile development world, when you’re developing a brand new product, think very hard about what your app is really all about. Could you take it to market with all the important features, or with features that are less functionally rich, in a fraction of the time?

Apart from reduced cost, reduced risk and higher benefits by being quicker to market, you also get to build on the first release of the product based on real customer feedback.

So all of this is really common sense I suppose. But it’s amazing how often development teams, with all the right intentions, over-engineer their solution. Either technically, or functionally, or both.

The really tough question, however, is can you see up-front which 20% is the important 20%? – the 20% that will deliver 80% of the results. In very many cases, the answer sadly is no.

original content from here