Knowing others is wisdom, knowing yourself is Enlightenment.

Reading other people is a skill you can get good at from outside, and it is genuinely useful. Turning the same attention inward is harder, because the instrument doing the looking is the thing being looked at, and every observation arrives already shaped by what you would prefer to be true. That is why people can be shrewd about everyone in the office and blank about their own patterns.

The workaround is other people. Ask two who know you well what you consistently do that you seem not to notice. Then resist explaining. The explanation is the exact move that keeps the blank spot in place.