I think that, to some degree, this same logic works in the civilian world. The people who really were there on time shouldn't have to wait for you to get settled. If you just show up at that time, then you really are late, because that is the time that the operation was supposed to start. If you are supposed to be on watch at 1200, then you need to be at your watch station with a clean uniform, your weapon, and a completed turnover, ready to take the watch, at exactly 1200.

If quarters is at 0700, then that means you should be in formation and at attention at 0700. 2) On time means being in position and ready to go, not just walking through the door. In a job where you can literally lose your life because someone was late at the wrong time, it is considered important to drill into people's heads that being late, or even 'just making it' is unacceptable. 1) operations are sometimes trivial and sometimes so important that they are literally life and death. In that situation, it is largely for two reasons. I must have heard it at least 500 times when I was in the Navy.

This is a common phrase used in the military.

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