Incomplete Library Class.
Sooner or later, libraries stop meeting user needs. The only solution to the problem—changing the library—is often impossible since the library is read-only.
##Signs and Symptoms
Sooner or later, libraries stop meeting user needs. The only solution to the problem—changing the library—is often impossible since the library is read-only.

##Reasons for the Problem
The author of the library hasn’t provided the features you need or has refused to implement them.
##Payoff
- Reduces code duplication (instead of creating your own library from scratch, you can still piggy-back off an existing one).
