I do check my car every couple of weeks. I have a routine that takes about 3 minutes total. About twice a month so about 24 times 3 minutes ~ 1 hour per year.
Although I could argue it actually takes zero time because I usually do this while waiting for somebody else to get into the car.
As a side note, if you are too busy to brush your teeth you should consider talking to a health professional about consequences of not brushing teeth. Or maybe your wife/girlfriend.
I also inspect my car pretty regularly in a quick "walk-around", and check things like tire pressure at least monthly, if we're out here collecting anecdotes.
I just check my lights in either glass window reflections or paint reflections from parked cars depending on how and where I’m parked.
The only car that needed the engine oil checked regularly was our second car, a 12 year old Opel Corsa. All other cars kept their fluid and just needed the oil changed at the regular intervals.
My 2000 model Audi actually has a indicator light on the dash that only comes in when the stop lamp is not coming on, but only when the brake pedal is pressed.
Although I could argue it actually takes zero time because I usually do this while waiting for somebody else to get into the car.
As a side note, if you are too busy to brush your teeth you should consider talking to a health professional about consequences of not brushing teeth. Or maybe your wife/girlfriend.