Assign a responsibility so that cohesion remains high.
How to keep complexity manageable?
In terms of object design, cohesion (or more specifically, functional cohesion) is a measure of how strongly related and focused the responsibilities of an element are. An element with highly related responsibilities, and which does not do a tremendous amount of work, has high cohesion. These elements include classes, subsystems, and so on.
A class with low cohesion does many unrelated things, or does too much work. Such classes are undesirable; they suffer from the following problems:
hard to comprehend
hard to reuse
hard to maintain
delicate; constantly effected by change
Low cohesion classes often represent a very “large ...