How common is wound seperation as a complication

I see a lot of wound seperation posts on this thread, but I cant tell if that is because its very common or because its very disconcerting when you have it so people want to share it more often than people where everything is going great. And is it more common if you get UL or does that not matter? Im assuming it doesnt matter because wound seperation just happens when you sew a new flesh tube onto your body in general. Not everything wants to grow on or grow shut right away.