Remembered Too Late
Characters often recall things when it would be just too late to actually use that information.
It could be an important code to use on a spy mission, or what not to say to a king when on a diplomatic mission, or what a guy is allergic to when making him dinner.
And those things can all be either Played for Laughs or Played for Drama. Also, the audience might be let in on this bit of information, or we might not. The former helps create suspense, while the latter comes as a form of The Reveal.
Heck, even a Crazy Prepared person or The Chessmaster isn't immune to this. A Cloudcuckoolander is very prone to this.
This can overlap with Now You Tell Me if someone forgot information they need to tell someone else.
This kind of thing isn't that implausible in Real Life, as anyone who tried to recall memories or information, and couldn't remember it until minutes or hours later, can attest.
Remember that this is forgetting something, not being given information one didn't know before.
A Super-Trope to Forgot I Couldn't Swim.
Compare Spanner in the Works, Something We Forgot, You Are Too Late, Repressed Memories, Remembered I Could Fly.
Contrast Just in Time, Photographic Memory.
Comic Books
- A few gags on Millie the Model involve this. One was her getting ready to model for a huge cigarette campaign, and then remembers that she doesn't smoke.
Literature
- In Under the Dome by Stephen King: As police chief Randolph and a detachment of officers are heading towards a meth lab in order to assault it and take the valuable propane stored there, Randolph realizes that they had forgot to grab body armor (i.e. bullet proof vests) before driving to the lab. He doesn't worry too much about it, since he figures the assault will be easy; he assumes the two men there will be too stoned out of their minds to fight back. How wrong he turns out to be.
- In The Princess Bride Miracle Max has promised that the miracle pill he made for Westley will last for a full hour. Its only after our heroes have left that he realizes that he messed up the proportions of ingredients and if it lasts for forty minutes it'll be a miracle. This is what causes Westley to collapse during the confrontation with Humperdinck. This was altered in the movie because to the grandfather would have to give timestamps.
- Early in Harry Potter, Sirius gives Harry a Christmas gift, telling him it can be used to contact him in an emergency. Harry utterly forgets about this until well after misinformation from Voldemort gets Sirius killed, something which could have been easily prevented with the use of that gift.
Manga and Anime
- According to the first Magical Girl Lyrical Nanoha Compilation Movie, this is the Tragic Flaw of the Big Bad Evil Matriarch Precia Testarossa (this bit of her characterization differs from the original anime). As she plummets to her death, she suddenly remembers that her beloved late daughter Alicia wished for a little sister--in other words, she wished for Fate, whom Presea treated like crap and rejected earlier. She then muses to herself on how she never notices things until it is too late.
Theatre
- In A Funny Thing Happened on the Way to the Forum, Pseudolus is trying to read a recipe for a potion, and then remembers that he can't read. Fortunately Hero is right there to do it.
Webcomics
- In The Order of the Stick Roy asked an oracle a question, and then realizes his question was poorly worded based on extraneous interactions with the Oracle, and worse, he immediately forgets even that the question was poorly worded, due to a memory spell in the oracle's home which erases all memories about the visit except one's question and the answer (including knowledge about the memory spell).
- Which leads to some Fridge Logic about why he kept walking out of the valley" instead of turning around immediately (since he hadn't had his memory affected yet since learning about the memory spell).
- In Gunnerkrigg Court, Annie's order for Reynardine to shut up is treated as Something We Forgot, but it also stopped Rey from telling her about the possessed Robot.
Western Animation
- In Adventures of the Gummi Bears, Cavin takes some Gummi Berry Juice to fight some trolls, and when nothing happens, Gruffi just remembers that the juice only works for humans once a day.