Why do people feel the need to state the obvious?

@SW-User Intellectual curiosity.

@MarkPaul ok I'll explain.

Contrary to widely held belief, the 'obvious' is not 'obvious' to everyone! 👌

@SW-User That's a bit flimsy. If you proudly announce the earth is round, you might suggest that there are some people who genuinely think it's flat. But, still that would be a statement of the obvious.

I'm not looking for superficial answers. I am in search of genuine truth.