Being a total newbie to fiberglassing, I did a horrendous glass job on my car. Air pockets, and doubled-over glass since I measured once, badly. I mis-read the directions on the box and applied both sheets at once instead of one at a time. Fortunately it's where nobody can see it on the underside of the rocker panels.
Ultimately it will end up undercoated.
My question is: how long can I expect this hack job to last before it needs re-doing?