O'Reilly logo

Extreme Programming Explained by Kent Beck

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Chapter 23. 20–80 Rule

The full value of XP will not come until all the practices are in place. Many of the practices can be adopted piecemeal, but their effects will be multiplied when they are in place together.

Software programmers are used to dealing with the 20–80 rule—80% of the benefit comes from 20% of the work. XP makes use of this rule itself—put the most valuable 20% of functionality into production, do the most valuable 20% of the design, rely on the 20–80 rule to defer optimization.

For the 20–80 rule to apply, the system in question must have controls that are relatively independent of each other. For example, when I tune the performance of a program, each possible place I could tune generally has little effect on the other places ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required