滚动时UIScrollview调用superviews layoutSubviews？

I added a UITableView as a subview to a custom UIView class I'm working on. However I noticed that whenever I scroll the table it calls my classes layoutSubviews. I'm pretty sure its the UIScrollview that the table is inheriting from which is actually doing this but wanted to know if there is a way to disable this functionality and if not why is it happening? I don't understand why when you scroll a scrollview it needs its superview to layout its subviews.I added a UITableView as a subview to a custom