There’s a saying in Yiddish “m’ken nisht a mench biz m’lebt mit im” – you don’t know a person until you live with him.
I can think of quite a few people (including myself) that could be described by others as “quiet,” “shy,” and “reserved.” However, I can also tell you that most of these people have plenty to say and can even be quite hyper at times – just give them a chance to get comfortable.
But the “quiet” boys and girls also have to be considerate of the person their dating. It’s very difficult to carry a conversation with someone who doesn’t volunteer any information and only responds with one word answers, such as “yes” and “no,” when asked questions in an effort to engage in a conversation.