revolving door 
noun
1An entrance to a large building in which four partitions turn about a central axis.Follow the path around to the building with the revolving door, take the elevator four flights up, follow the hallway down and enter the second room on the right and watch me on the couch interviewing at Juilliard....
- Presenting his back to Serena, Ethan walked through the revolving doors of the building and disappeared inside.
- Wordlessly, he stepped through the revolving door and into the building.
1.1Used to refer to a situation in which the same events recur in a continuous cycle: many patients are trapped in a revolving door of admission, discharge, and readmission...
- She urged the provincial government to implement addiction treatment to end the revolving door cycle of women's incarceration.
- Unless they're going to lock up drunks and throw away the key, such a policy will simply create a revolving door situation, with as many itinerant alcoholics being released from prison at any given time as are being locked up.
- The team used seven starters in right in 2000, and the revolving door could continue.
1.2 [usually as modifier] An organization that people tend to enter and leave very quickly: the newsroom became a revolving-door workplace...
- Moyes had claimed at his unveiling that he wanted to bring some stability to the club after the revolving door transfer policy of the last few years, but these hopes were dashed with the abrupt departure of Paul Gascoigne to Burnley.
- Most businesses can't afford that sort of revolving door operation.
- Who do you want to knight you, one of Italy's revolving door leaders?