Our nearest big supermarket is an Asda, I have shopped there for most of my shopping for at least 10 years, probably more like 15. Over the last year to 18 months it's gone rapidly downhill. Although the fruit/veg sections are usually pretty full, there are large gaps in many of the ambient shelves. Random stuff like salted rice cakes I haven't seen in weeks. They seem to have people working filling the shelves during the day rather than in the evenings like they did previously. Cleanliness standards in the shop has slipped. They have started using the most awful muzak instead of artists/songs you'd recognise.
People love to moan about Brexit but none of the other local-ish stores seem to be having these issues. Yes there is an Aldi fairly close by which I'm sure has poached some of the custom but it can't be the full explanation - is this just our local store which has a crap manager, or a more general issue?