The whole "forgiveness" ordeal has a double function and a double audience:
1) It draws in the lowliest of scum, the morally weak, the cheats, the liars, the typically lazy and bad parents, and offers them an easy way out from actually confronting the shit they do. They say that it encourages self-reflection, but it's a complete lie. People's eyes are fixated on the prize: a get out of sin card. "Yeah, I'm a shit human being, I let the TV parent my kids and I beat them when stressed, but hey, I bring them to church twice a year and God will settle this shit for us" - and everything continues as usual. Note that this is for those who aren't really into Christianity, they are mostly outside sympathizers, drifters, fellow travelers, etc. Still, they are drawn in by this superstitious belief that you can just flush away your sins every now and then. Their approach towards their conscience is that of your approach to your hand's hygiene.
2) Then there's the soul crushing aspect for the hard core Christians, who are usually indoctrinated into it from an early age. They develop constant self-doubt, list their sins at the every end of the day and pray for forgiveness, approach the most basic decisions based on how sinful they are, and so on. They are way beyond superstition, it's a never ending lifestyle for them. Their habit is formed since a very young age, like when they teach prayers to 3 years old who can't even comprehend the words, or when they restrict what kinds of friends they can have, what kinds of books you can read, etc. The best parallel would be the addict: at the back of the mind of the addict there's always a lingering thought on where to get the next fix, how to avoid the cops, a continuous calculation going on in their heads about a lot of risks and a very few and temporary gains. They put aside the thought how burdened they are by the drugs, but the indoctrinated Christian, the forgiveness addict, can't even do that, because he was never offered a critical tool set or an alternate lifestyle to even realize that his fellow human beings don't have this constant and quite frankly foreign invasion going in their heads all the time.