Why the boundary is a door rather than a description
Descriptions drift. A scope that says the warehouse and associated areas will, within a year, be asked to cover a strip beyond the door, then a staging bay inside production, then the area around a machine. Each request is small and reasonable in isolation, and together they move a cleaning crew into an environment with hazards and requirements the scope never contemplated. By the time anyone notices, nobody can point to when the change was agreed.
A door is unambiguous. Everyone can see it, a new crew member understands it immediately, and requests to go beyond it are visible as changes rather than as gradual expansion. Where the client genuinely wants production cleaning, that is a separate conversation with its own assessment, its own inductions and its own method, and treating it that way protects both parties. It also gives the client a clean basis for pricing that second scope if they want it.
