You want to buy a second-hand car. What's the first thing you check? Yep, the mileage. The cost of a car is basically down to its depreciation, which is basically down to its mileage.

It's not only the mileage. Age is very important too. Look at any car advert - it's the age that is highlighted first. Mileage only if it is unusually low.

Many components degrade simply due to time, especially things like rubber seals.