If it’s an expression “everybody uses,” it’s a cliché.
If it’s the first phrase that comes to mind, it’s probably a cliché.
“It’s a cliché because it’s true” is no excuse. And it’s a cliché.
If a sentence contains a cliché, no one will ever remember you’re the one who said it.
I tweeted those lines a few months ago, without much forethought, probably triggered by coming across a stale expression one time too many in something I was editing. It was no shock to me how I felt—I’m constantly telling students, “You can always do better than a cliché.” (Actually, that could be the fifth point.) What surprised me was the admonition that if a sentence contains a hackneyed phrase, no one will ever remember you’re the one who said it. The idea you’re trying to express, that is—plenty of people may remember you’re the writer who settles for clichés!
We all want our writing to be memorable. For the right reasons.