Are you near sea/salt water, or in general they just don't last. Sounds like if you driving a mercedes, you need a garage. I get snow n ice here so nothing worse than clearing that shit off at 6am rushing to get to work.
I went to auction at a mom/pops video game store few months ago that was closing, and bought 11 slims for $200, 1 was DOA but 10 work fine. so hella deal.