In Medlars, A perfect small garden tree with fruit best eaten once it's gone rotten (Guardian, November 2010), Alys Fowler notes that medlars and marmite have one thing in common. People either love it or hate it.
No grey area.
Medlars are catalogued as Mespilus in Wikipedia's introduction below:
"Medlar (Mespilus) is a genus of two species of flowering plants in the subfamily Maloideae of the family Rosaceae. One, Common Medlar Mespilus germanica, is a long-known native of southwest Asia and possibly also southeastern Europe (Black Sea coast of modern Turkey), and the other, Stern's Medlar Mespilus canescens, was recently (1990) discovered in North America.
The Common medlar features an unusual apple-like fruit that requires bletting to eat; although not widely eaten today, consumption of these fruits was much more common in the past."
Alys Fowler understands that shopkeepers are not keen to stock a fruit that would require a 'leave to rot' tag while on display.
So as not to upset anyone, the medlars above are pre-rot stage.