Another point not mentioned yet - bodywork / chassis corrosion ...
Whilst the general standards have vastly improved with more use of plastic [I remember the old Lancia] - a few decades ago engines would outlast bodywork - did I hear right that the UK is now the ONLY country in the world still putting SALT on the roads to deal with snow and ice? Once that gets into your steel chassis it's only a matter of time - 10 years of UK winters used to do for many a decent motor, but not so now ...
better quality modern cars are well protected . . . . one of my cortinas was re-imported from France 10 years ago, never seen salt, and little rain, no rust, and original paint . . .its 56 yers old.