I blew up a rear rim on my road bike once.
I knew the rims were wearing out anyway but on a descent the brakes weren’t sounding right so I stopped and checked the bike over and the rim was paper thin.
Let a load of air out to reduce pressure on it, turned round and carefully rode back up the hill. About 100m from my house, the rear wheel just exploded, blowing out a third of the rim section in metal, ripping the tyre and tube to shreds. Dread to think what the result of that would have been at speed or if I’d been 50 miles from home!
Wrecked an ISIS BB on the MTB once (the whole shell cracked, bearings fell out and it left the axle rattling round with no support), again fortunately was near the car.