Flaking is usually due to improper prep before applying the coating. Even if there is wear, it should not flake. Sometimes it can even come down to which media is used to blast it and if it's clean. Sand and glass beads have shown problems and aluminum oxide seems to be doing better. It all comes down to how well the surface was prepped, if it was sprayed cold and baked correctly.
Malo periculosam, libertatem quam quietam servitutem." (I prefer the tumult of liberty to the quiet of servitude.). Thomas Jefferson
"All that is necessary for the triumph of evil is that good men do nothing."
-Edmund Burke, Loosely translated from Thoughts on the Cause of Present Discontents. (1770)