Why are mini roundabouts ok in some places because they keep traffic flowing. yet not ok in other places?

Question

in england councils install mini roundabouts because of traffic build up in the hope there are less accidents and traffic flows. yet if this is good for one area why do they not do it everywhere. Logic dictates that this must be a good idea for every junction in towns and viiages.

Answer 1

As long as each little town council can decide whether to accept mini-roundabouts, the issue will exist throughout England.