A Christian recognizes that s/he sins, and asks God to forgive him/her. A Christian is not expected, and does not expect, to be perfect. Sin > ask for forgiveness > try to better yourself. By being human and making mistakes, then asking for forgiveness, they actually are following the Bible "all the way."
The problem with a lot of Christians is that they don't recognize that many things that they have personally made into a habit are considered sins in their holy book, yet belittle homosexuals because it's not normal and "against the bible." I have a friend who exemplifies this.