information that would have been useful 5 minutes ago

Did you ever see someone trip on the streetcar or cut themselves in the kitchen, and after they've done it you say "Ooh, be careful!"

How useless is that? That's a warning that would have been useful about a minute ago. It's like someone falling off a roof and then you tell them "Ooh, you should be careful up there" as they wait for the ambulance to show up.

Somewhat different is someone consoling you after you've been dumped, broken up with someone, or left at the altar. "That guy/girl wasn't right for you, they were a jerk." In that case, yes, it's true and you could have be told that weeks or months ago, but would you have listened? No, probably not, because you would have given the same reply as the guy on the roof who you warn ahead of time to be careful: "I know what I am doing."

No one wants to be told they have bad judgement, but I think recognizing it is a step in the right direction. Or at least keeps your feet on the roof.