One of the things that has to be done when painting flexible parts is to make sure the flex additive is added to the paint mixture AND in the right amount.
My brother needed a new nose cone on his '80 T/A. It looked great when he got it back from the painter.
About a year later, little cracks started to appear, especially in the headlight pockets. The cracks started getting bigger and soon after the paint was flaking off.
We were told the by a very reputable body shop that the painter (uncle of a friend) did not use enough flex additive in his mixture and that's why the paint was cracking and flaking off.