Because cars have had consistent keys and doors for how many years now? That's half the thing about cars - you shouldn't need to read the manual to know how to

Because cars have had consistent keys and doors for how many years now? That's half the thing about cars - you shouldn't need to read the manual to know how to open a fucking door. Maybe for service timings, etc, but you should be able to get into any car and be able to use it for completely normal use cases *without* reading a manual.