Most people make mistakes, but without seeing clear consequences, they make the same mistakes over and over again.
A website forum that allows people to discuss the mistakes they’ve made and solutions. The money would be in the categorization of mistakes so you could easily find problems you’re dealing with.
You are about to make a critical decision and you want to know what has happened to others. The site is well organized so you find the problem you have and see if you’re making a wise decision. You make the right decision because of help from the site, so you happily engage with others as well. Users that are engaged in the site would be rewarded with points.
Learn from your mistakes, don’t live in them.