Obvious, I know. Yet, there's something genuinely fascinating in an effort we are ready to make when we are starting to talk to someone. Not sure whether it just aims at impressing that new acquaintance of ours, or because it's part of our New Year's resolution to stop being so inappropriately modest...
The result is, we want to be admired by someone we don't yet know. So we put our best smile on, we reveal the best vocabulary sets we have ever known, we even add a bit of non-flirting charm. We try.
Why then, it's practically never the case with the closest ones? We use simple words, we don't dress to impress at home, and the charm... well, it's best kept. Hidden. For another stranger who happens to be passing by.