paint cracks, older it is its easier for it to crack. There nothing you can do about it if it does, they do their best not to let that happen. Thats why Curry's or CDE they both make you sign waviers that say their not responible if it does crack.
If your car was repainted by a body shop it has more of a chance of cracking. If i fix the camber on my car the fenders has to be rolled but i'm not taking the chance of the paint cracking.