London's a special case: every single unit that can be converted from "affordable housing" to "luxury accommodation" is a massive profit realised by the develop

London's a special case: every single unit that can be converted from "affordable housing" to "luxury accommodation" is a massive profit realised by the developer. You can make a lot of money from building low-cost housing, but you can make an awful lot more from building really expensive housing, because there is essentially unlimited demand for both.