Dld. I dont think everything is perfect. Regret happens when things dont go our way. Life does not get prettier. Everything happens for a reason and that reason is the test of life.
Life of the world is not a place of happiness or sadness but a medium place a balance between heaven and hell.
Regret happens, things dont go our way, because if they did we wouldnt be able to handle them. E.g you may want to be a Hollywood actor, but you may not be able to handle the fame, so you are not strong enough, so things happen which prevent you from becoming it, and we put that down to some excuse, and regret it.