SWMBO has been consulted and confirms that washer dryer combinations are abominations from a usage point of view. I can confirm that the one we had was the least reliable thing ever purchased. Bosch one so you might expect reasonable quality. Not so and therefore Miele only from then on.
Seems to be down to the luck of the draw as much as anything.
I’ve got the cheapest washer dryer you could buy from Indesit, and it’s been running like a champ for seven years.
My wife is not exactly know for mechanical sympathy (as two clutches broken and another now slipping within 50,000 miles on her car will attest) so you can guarantee it’s been massively overloaded and set with everything up on full blast when she uses it.