It depends. Minimizing and canceling drift can be very simple or can be sophisticated rocket science. It depends on the source and size of drift. Usually, it's the more tricky to compensate for drift the less drift is desired. There cannot be given a general answer. Each area of electronics has its own tricks to cancel drift.

Please rise a more specific question.

With the example of your power supply: Usually, there's no need to have way less drift than tolerance of output voltage. If the tolerance is specified to be less than +/-5% under all circumstances, for instance, then there is no need to have a drift of way less, provided the tolerance of +/-5% isn't violated by the drift.

On the other hand, if you need a power supply showing very low drift, then the usual procedure is to order a power supply showing very little tolerance, and by this very little drift.

Kai Klaas