Why service corridors are the classic gap
They serve everybody and belong to nobody. A retail tenant uses it to move waste, a resident uses it to reach a bin room, a delivery driver uses it as a route, and a building manager thinks of it as back-of-house rather than as a cleaned area. Every party's cleaning arrangement was drawn outwards from their own space, leaving the corridor at the margin of all of them and inside none of them. That is a structural gap rather than an oversight by anybody in particular.
The result is a space that receives attention only when somebody complains, which in a back-of-house area takes a long time. By then the floor has accumulated real soil, waste has been left along one wall, and the condition takes a substantial clean to recover rather than the routine attention it should have been receiving all along. Recovery then costs far more than the routine attention would have.
