alternator

I changed an alternator today on a y reg fiat chickentikka (chiquecento i think) 19000 miles on the clock
my mk1 diesel has the origional bosch alternator and starter motor after 23 years,and my gx had an engine put in by me out of a W reg jetta with 40,000 miles and the origional rotating electrics are still on doing just fine with a date stamp on the starter casting on 1978
If bosch can do it why cant everyone build a car as good as a vw?
bert