> Then wouldn’t these be left alone ? The problem is that you don't know which ones would never develop into anything if left alone. The reason they're left a

> Then wouldn’t these be left alone ? The problem is that you don't know which ones would never develop into anything if left alone. The reason they're left alone now is that you don't know they're there, because you never do any test that shows them being there. But once you do a test that shows that something is there, it's a lot harder to just leave it alone. Something is there, and you don't know that it's never going to be a problem, so you end up not leaving it alone. If you were going to leave the thing alone anyway regardless of what the first test showed, there's no point in doing the first test at all.