Why people refuse to believe God exist

There are alot of Christian topic being formed all around but no one has yet said their reasons why they don't believe in God.

Is it just because you can't see God that you feel he don't exist, or because you feel nothing should be greater than humans, or you don't just want to believe God exist?

God exists only in the mind of people who believe. It exists as an interpretation of something we cannot and never will understand. Though it will never, ever represent truth. Because we will never know, it's nothing more then a thought. ( that has been abused by religions for many ages but that to the point )

It's much better to focus on life itself, rather then pretending having answers on questions that can't really be answered because our knowledge has a limitation. Believing in God is a waste of the potential of the human mind. So I obviously don't believe,