1) their true self scares them
2) they are afraid their true self scares other people
3) because its just easier to conform to what's normal. everyone's weird in their own ways
4) because some people are just evil. we all are. we just keep the devil within
5) because we all have secrets. big or small, serious or frivolous, we hold on to our little secrets
you know, don't even bother to 'un-mask' someone. maybe sometimes it's best not to know.... If not, usually your instincts and intuition tells u if that person is being his/her true self. we sometimes just choose not to trust our instincts.