The overzealous person that screams a bit too loud in the ears of a new convert, scaring them, must be more fully prepared by God to be more effective. The overly shy believer who cannot move out and help someone at the altar must be refined and broken to be used by God. All of us have to be broken. That is only two steps of four complete steps. God does not take us out to simply bless us, although that is all you will ever hear some tell you.
Every joint is supposed to supply something to the work of the body.
But everyone will do something. We ask all to come to the altar, because we are seeking not just folks to come and pray who have an area they need to pray about, but because there are others whom God wants to use to help others in this altar. Pray for wisdom. Pray for usefulness. God wants to use you to help people.