No common sense (London)

Wood Green Tube station on the northbound Piccadilly line has three escalators.  

Normally, the middle escalator is at rest.  

The down escalator is closest to the southbound platform, which makes sense, as people going from Wood Green are more likely to go south (heading for Central London and Heathrow Airport) than go north (with only five more stations after Wood Green).  

The up escalator is closest to the northbound platform, which again makes sense:  people disembarking at Wood Green would be more likely to be on the northbound train from Central London, as evidenced by the huge crowds spilling out from the northbound train, especially at peak hours.

The previously-down escalator is recently under some sort of refurbishment, so it’s all boarded up.

For some reason, instead of letting the middle escalator take on the down-moving role and leave the up escalator as it was, someone decided to switch it round, so that the escalator nearest to the northbound platform is now down-moving.  This means that people coming down, who are more likely to catch the southbound train, end up cutting across the now-up escalator for the southbound platform, and people getting off the northbound train are cutting across them to get to the middle escalator, which is now the up escalator.  

The result is two streams of passengers interweaving with each other.

The station actually put up signs on the boards alongside the now-shut escalator, saying: 

QUOTE To help you travel through the station more quickly UNQUOTE

The left hand obviously doesn’t communicate with the right hand here.

(London, 2018)