What is modifiability?

The architectural quality attribute of modifiability can be defined as follows:

Modifiability is the degree of ease with which changes can be made to a system, and the flexibility with which the system adapts to such changes.

We discussed various aspects of modifiability in the first chapter, such as cohesion, coupling, and others. We will dig a little bit deeper into these aspects in this chapter with some examples. However, before we dig deeper, it might be a good idea to take a look at the big picture of how modifiability fits in with the other quality attributes that are related to it.