In Moscow metro they sometimes ask (but do not enforce) via speakers to stand on both sides of the escalator. I heard this practice was brought by McKinsey from

In Moscow metro they sometimes ask (but do not enforce) via speakers to stand on both sides of the escalator. I heard this practice was brought by McKinsey from London. In my experience this sometimes works on very short escalators, and on the longer ones people seem to ignore the suggestions. I wonder about the psychological reasons of this behavior.