Why didn't anyone take care of this car?

I'm 17 and I'm looking at cars. I'm looking at all sorts of different cars. I was looking at the 2000-07 Ford Taurus. I noticed these cars sell for good deals with very low mileage. I've driven one and I didn't think it was a bad car at all. I noticed a lot of them I find online are quite beat up and barely have 150,000 miles on them. When I find a Mercury Sable, it looks like it was taken good care of. Why didn't people take care of this car?

Who cares

The Ford Taurus is the household staple car for anyone that needs a lot of room, does not have a large car budget and does not know anything about cars.
For all of these reasons, plus poor Ford build quality prior to 2007, they are often in poor mechanical shape when they hit 150K miles