Your standard should survive deadlines.

Deadlines are where standards get tested, and a standard that quietly lowers under time pressure is not really in place. Something does have to give when time is short, and it should be the scope rather than the quality, since a smaller thing done properly serves better than a larger one done badly.

When the deadline tightens, cut what you are attempting rather than how well you do it. Say plainly what will not be included. That conversation is uncomfortable once and much better than delivering something you would not stand behind.