Wikipedia defines the termination point of a GA to this:
Commonly, the algorithm terminates when either a maximum number of generations has been produced, or a satisfactory fitness level has been reached for the population. If the algorithm has terminated due to a maximum number of generations, a satisfactory solution may or may not have been reached.
Now, if it terminates when a satisfactory fitness level has been reached, and you are the one defining that fitness level, why wouldn't you just be able to create the "perfect" genome from the beginning yourself, since you already know the characteristics of this perfect genome?
I guess I'm just a little confused here. I thought the purpose of a GA was to constantly evolve and show us possibly an even better solution than what we thought of, and our fitness function was just something that helped it along the way, not something we put on the pedestal as the termination "perfect" state. Doesn't that destroy the point?