A no-show policy defines what happens when someone books a desk or room and does not turn up. The standard mechanics: a check-in window opens before the booking starts, and if nobody checks in within a grace period, the booking is cancelled and the space returns to the pool.
It is the highest-leverage rule in workplace management. Without it, your busiest days are partly an illusion of phantom bookings; with it, capacity frees itself and your data starts telling the truth.