I think my parent's main motoring quirk is they really don't have a lot of passion for cars and just buy what suits them, keeping it forever when they do. To be fair my dad had a few sporty Fords. I believe his complete motoring history is:
MK2 Cortina 1600E
MK4 Cortina 2.0S AMD253T
Saphire 2.0i GLS E962JRY
Passat TDI (now mine) R81HPU
Now he just shares a CRV and a Jazz with his wife. Bloody pensioners!
My mum has had even less and no brand loyalty:
Hillman Super Minx KYN465D
Dolomite 1500HL SBT546T
MK3 Astra GLS J337HME
MK3 Astra GLS auto L317LTW
The 2nd Astra had gone through the hands of a couple of my friends and not been used much, she decided she should go to an automatic as her health deteriorated, and finding the same car with a slushbox saved me having to explain over and over again how the new car worked. It does 500 miles a year if it's lucky