as problems or threats are identifies Ms issues a fix .... these fixes fix what's already there .... so if you don't use whatever it is that's been fixed .... you won't see anything obvious.
If the fix fixes a vulnerability to a particular set of circumstances ... again ... even if you do whatever it is that causes the problem .... because of the fix .... you won't see anything.
(it's a bit like elephant repellant - have you seen an elephant lately?)
it doesn't mean that you should stop though .... just because you haven't seen one - cause if you do stop........