A modern fuel pump in a petrol car is nothing like an old SU pump in a Morris Minor. The SU pump could possibly manage about 3 psi on a good day, a modern petrol injection pump is normally above 5 bar (70 psi) and they pump at that pressure all the time. The pressure is regulated by a regulator (believe it or not) on the manifold fuel rail nornally set at approx 3 bar, any excess fuel is allowed back to the tank via the fuel return pipe thus the pumping rate does not reduce when less fuel is used. If the fuel pressure dropped below the pre set figure the engine would run lean.

They can fail and when they do its replacement time, not normally repairable.

Morris 1000 pumps normally outlasted the car.

<Vapours>

Those SU fuel pumps were legendarily unreliable. They might well last "the life of the car" from the manufacturer's viewpoint, i.e. getting past the warranty period, but long term the points will become "iffy" and it'll stop working. Thumping it with a wheel brace can jazz some life back into it for a while.

I'll agree that while they work they're great, but once they start to play up, replacement is the only option.

There is a very good reason why aftermarket solid-state alternatives are available to this day.