Par Time
The fixed time limit a stage allows for firing the required shots, after which any rounds not yet fired are scored as misses.
Par time is the window a stage gives you to complete the required course of fire, and it defines the pace you have to keep. The clock starts on the beep from the shot timer and stops when the limit expires, so any target you have not addressed by then simply scores as a miss. In PRS and similar formats a typical stage par time is short enough that hesitation on a single position can cost you the whole sequence.
Because the limit is fixed, smart competitors plan a shot order and a movement plan before the beep so every second counts toward a hit. The squeeze is sharpest in positional shooting and on a barricade, where the time spent building a stable hold competes directly with the time spent actually firing.