Onur Cobanli explains:
I said this many times, and I repeat it once more; design is an iterative process, and it is like an optimization problem in mathematics, in general what happens is that most designers find a local maxima; local maxima is when the value of a function is greatest within a specific interval, however there could exists a global maxima or another local maxima with even higher value; now let’s assume that your local maxima is good design, if you stop design iteration at your local maxima, you will never arrive at a higher another local maxima let alone the global maxima, good design is the enemy of great design as in most cases you stop iteration when you have something good all while you may be a step or two away from truly great design.