Inventing fire
I’m really hoping that this is one of those signs in a non-English speaking country and it’s a misunderstood translation. I’m pretty sure fire is hot in all languages, though. Again, I am left with the feeling that there is a reason behind this sign.
Who leaned up against the grate, realized they were slowly getting warmer, or possibly that they could smell smoke? Who, after realizing that they were on fire, complained to the management that there really should be some sort of warning. You’d think that using common sense would be enough.