I'm not going to name names, but I'll just say that what I'm about to show you is actually destined for a real live actual television show, with actual famous people on said show. However, if you've ever wondered why sound people are special, it's because we do our best to avoid things like this:
This is a spectrogram of a clip of dialog. See all those shadowy spaces that make lots of horizontal lines? That's what audio people call "comb filtering," and it sounds terrible. This is most likely the result of a mic going into a mixer (or camera) and being combined with itself, but the 2nd signal had a slight delay - like a millisecond or less. Headphones, people! Listen to your sound before you hit record!
Not good.