Why do folk think I neglect our cars?

Because they service theirs four times as often, and they haven't had a problem either, so you clearly don't do it often enough, or are just lucky :-)

But how many stop/starts has it had? I bet the oil was in some state. I thought it deteriorated with use and age.

We've had this discussion many times, usually with John-F. Oil does not deteriorate rapidly with age if it stays fairly clean by using the car for trips long enough to get it fully warm. With short trips moisture and acidic combustion products accumulate. Of course 'use' for thousands of miles gradually breaks down the molecules mechanically. Hence the usual instruction to change oil after XX miles or Z years.

Towards the end of its sterling 17 year service our faithful old Honda did 800 and 600 miles in its last two years. I still had it serviced and MOT. Eventually SWMBO agreed that it was uneconomical and not fair on the car to do that sort of mileage so disposed of it.

Obviously what you do with your car (and who you Obey) is up to you, BUT

(a) I don't understand what made it "uneconomical", unless it was too frequent servicing, which doesn't seem to be your point, and

(b) I don't understand the "not fair to the car" bit.

I can relate to a non-rational emotional involvement with a machine,since I get that myself, but don't see how that goes along with scrapping or selling it.

Just me, I suppose.

I've had it 16 years says he, passes the mot every time. That's what regular servicing does says I, never had it serviced he says, only done 10,000 miles in it so it doesn't need it. Not even an oil change.

Lets look a bit deeper into this other than the simple fact its missed 16 oil changes.

I am pretty sure its a chain cam engine and normally they require fresh oil to ensure the chain is fit and well. A rattly chain is not an MOT failure but sure as hell means the engines on its way out.

If its only done 10,000 it almost certainly on its original tyres. At 16 years old they will be like concrete with a strong possibility of cracking. Cracks would be an MOT failure but age is not checked so the car could be legal with dangerously low grip levels in extreme weather and/or emergency situations. If the tyres are original the valves will be as well. Rubber valves harden and have been known to snap resulting in instant deflation.

Then there are the brakes. Other than checking for corrosion, leaks, piston movement and the handbrake operation the MOT does nothing other than check their performance. Any modern car should pass this test since the requirements are based on what an ancient classic should do on drums all round. As is frequently said on here brakes need maintenance to ensure they are working properly. And what about the brake fluid, at 16 years old it will not be at its best will it.

Then the non-MOT items. 16 year old antifreeze might still work as antifreeze but the critical anti corrosive properties for an alloy engine will long have been lost so what is the engine like inside.

Then there are the auxiliary belts. At 16 years old it is certain to have cracks. For a few pounds it could leave you stranded if it parts company at an unfortunate moment.

Yes, maintenance costs you money but that's life.

What worries me is if the owner of the MX5 does not maintain his car does he actually maintain his heating system. That is not a legal requirement for owner occupiers (it is for landlords) but its can kill owners as well as tenants.

The MX5 uses a non-interference motor so I suppose the risk of belt failure is lessened somewhat.

Cannot see how the engine design makes any difference. Belt failure will happen not because of the likelihood of valves and pistons trying to have a dance but due to age, manufacturing defect of associated component failure.

In the last 40+ I have only known 2 people who have suffered cam belt failures and one of those suffered 2.

First was a chap at work in a 1970's Audi 80. Failure was caused by the auxiliary belt breaking and getting into the cambelt area causing the failure. I cannot remember if this car had belt guards, it surely must have but in my experience there is no way this could happen, but it did. He was on his way to Luton to fly to Barcelona for a family holiday, bet his wife was delighted. No damage other than needing a cam belt and auxiliary belt after being recovered off the M1.

2nd was friends of my parents in a Escort Mk 3 1400 CVH. These were well known for belt failure and desctruction of the head a very minimum, theirs failed at 30,000 miles. Very large bill for new head.

3rd was the Cortina that was the replacement for my colleagues Audi. 1600 Pinto with about 100,000 miles at approx 5 years old. No damage, just needed a belt. He replaced that with a Mk 4 Escort with a push rod engine, what a shocking car.

When you think of the miles people I know have covered its a miniscule failure rate but it proves nothing. If all the remainder have replaced belts within the mileage/time limits they should have no failures.