Both tyres replaced on my former main commuter bike.
Pothole debris this morning caused a 5mm cut right through the sidewall of the rear tyre and subsequent immediate loss of all air in the tube. The tube was replaced roadside but kept to a low pressure to get home due to it bulging through the hole. This afternoon I put a boot in the tyre, re-inflated to the normal pressure and then immediately deflated it and binned the tyre as the damage was too big.
I'd already had to do something similar to the front tyre last year for a smaller hole in the main tread and it was also showing other cuts so this was binned as well for symmetry as the new rear tyre was a different brand.
Not happy as that's less than 3000 miles on a pair of GP4000s which still had plenty of life left in them otherwise.