Maintainability as a key factor in maintenance productivity: a case study

Software quality is not an end in itself, but a step on the way to efficient software engineering. Maintainability is a quality factor whose effects will be seen in the maintenance stage. The investment to add maintainability to the software product must be justified with a benefit during this stage, that is to say, an improvement in maintenance productivity. Otherwise, this quality characteristic will not be a method for efficiency but an end in itself, ignoring the objective of software quality. We expose a case study where costs and benefits of maintainability have been analysed. As a consequence, we propose a technique to apply these quality characteristics in an efficient manner.