Contradiction

It is estimated that over 2,000 people every year are sent to Hell accidentally only because they had forgotten some of the sins they had committed and had in turn forgotten to confess them. And even more unfortunate people had died this year before being baptized at a very young age and were also sent to Hell.
God provides no incentive to be a good person, if he forgives everyone who confesses their sins, even if that person is a repeat offender. Meaning that you can do it again as long as you confess the sins again.
And how do you know when you've actually been forgiven? What if you didn't magically confess your sins in just the right way? Or what if you forgot your sins from before you started going to church? And what if the sin was a complete accident, and you died before you could confess it?
The concept of forgiveness for your sins seems to be man made, if the theory has so many imperfections.