Singapore Q&A 19 November 2022 with Sayadaw U Tejaniya (36:30-37:42)
If the watching mind can be equanimous when observing unpleasant objects or unpleasant situations, it means that the mind is skillful at practice.
For the unskillful mind, when the experience is pleasant, the mind enjoys the experience and when the experience is unpleasant, it resists the experience. In both instances, the mind cannot be detached from the object.
If someone knows how to practice well, the mind can step back and watch regardless of whether the experience is pleasant or unpleasant.