Alternative view - I used to know a local bank's small business manager. She had a good idea who was hot and who was not, and in our area the tea rooms were insanely profitable.

These were light meal plus tea places of no notable distinction or interest - except that they were in a prosperous, quaint, and touristy part of the UK, on a significant A road.

They did very well indeed from a combination of passing trade and regular customers, even with plenty of direct competition in the immediate area - there were maybe eight of these places within a quarter mile of each other.

Rents were relatively low, minimum wage labour was easily available, and the ingredients were generic and not very expensive, but prepared with some skill, so the food was better than average, but not exceptional.

A number of owners set up successful businesses and handed over the daily running to the staff. They'd literally turn up once a day, collect the cash from the till, and go home.

There were some failures, but owners were more likely to leave because they moved - often abroad - than because the business failed.