@Icon,
Don't know about others, but growth strikes me as an accumulation. You grow by having more experiences, more knowledge, more emotions, and in general just facing the unknown. Why, if you were to stay in a room somewhere and never go out of it, you'd stay just right where you are, not growing.
It also strikes me then that as we are rational beings, the more we accumulate, the more mature we become, it seems. In fact, I don't think growth itself is the maturing process--perhaps maturity is the result of processing and digesting new experiences honestly and intelligently.
Kind of makes sense when you consider the word "grow" originates from eating and physical growth. Only later did it accumulate it's psychological definition.