2 Blown belts in ~5k miles, alternator's fault?

I have gone through two belts in the last 2 months both seemed to burn up and snap leading to a low voltage indicator.

I have an aftermarket alternator from a brink and mortar store because I was dailying the car at the time and needed a new alternator.

Both times the belt has snapped its been right after really heavy rain storm that the car got left out in but there's obvious residue from a belt being torn up.

I don't have the splash guard whoever had the car before me removed it. Could something be shorting causing the alternator to bind up? That sounds ridiculous to be since I'd assume water damage to the alternator would be permanent but the pully spins fine and once I get another belt on it's fine.