I always wondered why cars are sole measured on milage rather than operating hours. Also maintenance wise but especially for the used vehicle market.
"normal'' people expect paying top dollar prices for a low milage car will guarantee them to be fault/problem free and that a high milage car will be a money pit for sure where it will be a question if it will even make it to the next mile.
I always bought the fully specced high milage cars for useally atleast half to 1/3 of the price that they ask for the low milage ''bare'' models.
Of course my car (bmw😁) also has problems/needs regular maintainance, but if i compare it to the other people that post the same problems on different forums i am amazed that people useally have the problems i get for example at 200k miles which they report on their car with having 80k miles.
For example oil filter housing gasket, which is an o-ring between the oil filter housing to engine block, this is constantly being compressed and just stiffens by age/heat/cycles.
In my opinion this is more age/hours related then the miles, the part doesnt care if 1000 miles have been driven or 300k miles.
A car that does a 1hr commute everyday traveling 80 miles compared to the same car that does a 1 hour commute every day trying to get to the other side of the city and only covering 15 miles in traffic jams.
Both run an hour a day, after one year the first car will have 16.000 miles, the second car only 3000. However both have accumalated 200 hours.
After 10 years the first has 160k miles, the second one 30k miles. Both have 2000 hours. The one fetches a lot of money, the other is considered a money pit.
My personal experience is that the vehicles that travel a lot of miles useally have interiors that are like new compared to city cars which only do short trips, also people that use their cars to travel long distances useally are more keen on looking after it and are willing to spend more on maintance because the car/realiability is more important to them.
Comming back to the question, the car that spends the 1hr 80 miles on the highway each day will get their fluids/oil to operating temp which will vapour of the moisture in the oil and gasoline dilution.
The car that only does 15 miles 1hr each day will spend most of its time with a cold engine which prevents the oil from vapourising the moisture/fuel. Also people then generaly do not consider to change the oil because they think it only did 3000 miles anyway.
I am almost willing to bet that a lot of the engines that we see that are fully slugged up are short milage/slow driven cars.
Aircraft/helicopters, agriculteral machinery, generators, boats, dirtbikes, plant machinery etc... are all measured in hours for their maintenance so in my opinion it would be wise to do cars too for atleast fluid changes, things like tires/brakes etc.. are more milage dependend.