A possible new trope I've been thinking of.

Exactly What It Says on the Tin:

A possible new trope I've been ruminating on.

A character gains some information, or makes a deduction about someone or something.

Knowing this, they take some logical steps to counter whatever problem is taking place, acting cautiously and intelligently.... and they fail.

Despite being right in their assumptions, and taking the logical steps, it doesn't help.

Why do they still fail? Maybe the info they had wasn't quite enough, maybe the enemy was still too strong for them, or maybe they were just really unlucky, but the fact of the matter is, their caution didn't help at all.

One example: Full Metal Alchemist Brotherhood (and the original manga) had Roy Mustang destroy an entire room to kill Lust. He's sure he incinerated her due to recognizing the smell of burnt flesh from his time the Ishval war. None the less, he tells his subordinate Jean Havoc to be careful, as she could possibly still regenerate.

Mere seconds after saying this, Lust, who is in fact in the process of regenerating, stabs Havoc In the Back.

Roy was right on every point, but his warning came too late, as Havoc didn't get the chance to follow his commander's orders.

That right there is an example of logic and caution not helping at all.

What do you guys think: Do I have something here?

Pardon the curt tone, but what I think is that your idea should go to YKTTW.

You can also check to see if we have this already using Lost And Found. Please heed the stickies on this forum though, it's a common enough mistake to propose tropes here and this isn't the proper venue for it.