Alot of people didn't believe until something swayed them against 'random theory.' Many astronaunts didn't believe, until they saw the Earth from space. Alot of times our heart and instinct get us killed. Our day to die could be at any moment. There could be an embolism heading to my/your brain at any time. Once you die, there's no rewind. Can't say, 'Oh God, I was wrong!' God makes his word known to all, and we have free-will to turn our backs on God, and many people, unfortunetly, make this choice. God doesn't force us to love him, that wouldn't be true love on our part. Like trying to force your GF to love you.
Those who aren't saved only have death to look forward to and this life is the best it will ever be for them. For the saved, this world is the worst it will ever be for us, and have no fear of dying; because we know our our 'fate.' It's comforting to know if a truck hits me head-on, while I'm on the interstate, I'm saved. The non-believer will never know this feeling, but thinks all those that die each day are always somebody else, and will never be them.
You won't be able to say in the after life, 'I didn't know.' especially if your reading this discussion.
You can't say to God, 'prove your existence and then I'll love you;' but if you open your "heart," he'll come in.