O'Reilly logo

Implementation Patterns 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 4. Motivation

Thirty years ago Yourdon and Constantine in Structured Design identified economics as the underlying driver of software design. Software should be designed to reduce its overall cost. The cost of software is divided into the initial cost and the cost of maintenance:

costtotal = costdevelop + costmaintain

Once the industry gained experience with software development, it was a big surprise to many that the cost of maintenance is much higher than the cost of initial development. (Projects with little or no maintenance should use a very different set of implementation patterns from those presented in the remainder of this book.)

Maintenance is expensive because understanding existing code is time-consuming and error-prone. ...

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