Look at it from God's point of view. What is the best way of keeping pride out of heaven? To make salvation a free gift, naturally.
But why is that then.
If you can get the kind of Godly righteousness needed for entry into heaven by proving to God how amazing you are, convincing and twisting God's arm and triking Him into thinking you deserve heaven more then others; it makes it makes you proud. You don't get into God's good books by exulting yourself and looking down on others who you think are less sinful then you.
God demands that salvation be by his power and grace and mercy and righteousness and holiness, not man's. Not in his interviews with God where he proves to Him how God-like he has made himself into. "Salvation is the Lords" but most people want to save them self rather then letting God do it, they want to be God. They are like the ground that thinks it can produce a plant if it is good enough without a seed.
Is your god truly God? or is he a pathetic weasel; cold and frightened scarred little runny nosed kid who needs to hold your hand for reassurance when he gets frightened and lost and can't reach you with his small arms. Is your God infinite in size or less. Do you take on some responsibility for God, taking up the slack where He runs short. Are you the kind of person who would stand up in front of God at the end and try to plead your case, try to convince God of things about you that He hasn't seen or can't recognize. Who's God is this, not our God, certainly not the great "I AM".
In the end God isn't interested in filling heaven with people who proudly think they can become more like Him due to there unusual human greatness, then the other scum. He wants people who simply believe that He exists, the all powerful, all graceful, all righteous, all merciful, all worshipful God exists.
