Keeping your mouth shut after an unimpressive introduction to someone protects you in two ways: 1) It guards you against being a jerk, and 2) it keeps your mind open to the impressive work they’ve yet to show you.
The best kind of impressive reveals itself over time, and not all in one showing like spectacle. We aim to impress with persistence, resilience, and growth more than with dazzling displays of skill, because dazzling is a form of hiding.
Likewise, we work with people more than once before writing them off. Our vision is limited, and we seek after our own image, which blinds us to ability we don’t share. So we stick it out a couple of times, so that people we don’t know can shine in ways we’re not apt to notice, and we trust that they’re doing the same for us.