It would be a close thing between my first car,a HB Viva,and my Sierra 2.0gl.
The viva went through 4 gearboxes and 5 clutches in about 9 months,but this was at ;east partly due to the fact that I was a teenager,so moving off from a standstill invariably involved revving it until the valves were bouncing merrily and then slipping my foot off the side off the clutch pedal sharply to break the traction in the big 145x12 tyres.

you could also sit beside it for a while and watcg it rust away,but it was my 1st car and I do have some happy memories of it so the award must go to the Sierra.I had it for 8 years while the kids were growing up,didnt really have much interest in nice cars etc,just working every hour in the day and raising kids etc,the car was utterly reliable,never did a thing wrong,only changed the oil about once every 3 years but it was the most bland,dull,tedious contraption I have ever driven.Hearing aid Beige inside and out and the engine should have come with a ventolin inhaler as it was completely asthmatic,didnt matter how much stick you gave it,it just wouldnt revup and go.