That's a pretty reductive assessment of what happened here. A system that requires you to remember to buy a window hammer on the off chance the doors don't open

That's a pretty reductive assessment of what happened here. A system that requires you to remember to buy a window hammer on the off chance the doors don't open is a system that has failed. We expect cars to have thousands of other safety features — we don't bring our own seatbelts in case the ones in the cars fail, and we don't wear helmets in case the airbags fail to deploy.