Knowing yourself means knowing your bad habits by name, not just your good traits by heart.

Ask most people to describe themselves and you get a list of virtues, slightly polished. The other column exists too and tends to be vague on purpose, a general sense of being sometimes difficult. Vagueness there is comfortable, and it also means nothing ever gets worked on.

Name three of yours in plain words, the way you would describe somebody else. Not sometimes impatient, but interrupting people when you already know the answer. Specific enough to catch in the act is the standard, since a habit you can see coming is one you can occasionally stop.