Sanding marks from improper sanding prior to painting. Ran into that on my last detail just last weekend, a Saab 93SE. Thank goodness it was white, they are barely noticeable. Still though, that's just as unfortunate as restray orange peel.
Honestly though, if I was to repaint a car, it would take months, I'd be sanding and respraying sanding and respraying... Admit it, many of us would be the same way, striving for that perfectly level finish.
