[Definition] This is the ability to enhance, extend, or replace pieces of the framework without requiring you to redesign the framework or your application. [Quality] 
Extensibility
S u b s e t a b i l i t y
L e a r n a b i l i t y
E x t e n s i b i l i t y
C o m p a t i b i l i t y
S i m p l i c i t y
T e s t a b i l i t y
P e r f o r m a n c e
S c a l a b i l i t y
U p g r a d e a b i l i t y