The design purpose of weapon degradation in Breath of the Wild is to let you have cool weapons without disrupting long-term balance or character growth. You can sneak into Hyrule Castle in the first hour and grab end-game weapons. Games never let you do that sort of thing, but BoTW can because it's just a short term boost.
It also fixes the dumb JRPG problem where the game won't let you grab the cool sword off a dead enemy because the game has *a plan* for your weapon upgrade curve.
@docky Yeah, all the upgrades in this game are a Big Deal
@mogwai_poet I love the way that the limited slots at the start of the game limit the usefulness of powerful weapons more than anything else.