1. You can compare a human being to a tight-closed tiny bud as like how humans don't open up easily and some people aren't impressed with them at first glance. But as time goes on, and they get to know them, they slowly open up.
2. Whenever you meet new friends, some of them don't easily see the beauty or goodness inside you because sometimes you don't open up easily or they can't/don't know how to tell that easily. As time passes, you slowly open up to them and they get to learn who you really it. (This question really depends on who you are. If you are a quick to trust person, you're probably the first part of the question and you should say, "My friends can easily see who I am as a person, because it is a part of my personality. I put my heart out and they see my 'beauty.'" If that fits you! If not, choose the first part I put and edit the you to I.)
3. In my opinion, I think it's better to reserve your goodness and let people discover it as time goes on and they get to know you instead of revealing it right away so they can't take advantage of you.