I confess that I have a stack of dud paintings in my studio that's about neck-high. Sometimes I'll pull one out of the pile and have a go at it with fresh paint and a palette knife. I tell myself that it's ruined anyway, so what have I got to lose?
Here's a photo of the ho-hum painting that I started with. I used the painting as my guide, and fractured and piled paint right on top of it. I prefer the newer improved painting so much more. I'd love to know if you agree!