D&D General How to make a villain not look stupid when players foil their plans repeatedly.

[Immoralkickass]

"'Twas merely a minor setback..."

 

[EzekielRaiden]

Respect.

Have them acknowledge the smart things the PCs did and correct the flaw they exploited in the previous plan.

Yeah, this is a huge part of it. Some other elements--which I will freely admit, I'm cribbing from Red (of Overly Sarcastic Productions) and her "Magnificent Bastards" video:

• The villain must keep their cool. Nothing damages the perception of magnificence more than flying off the handle.
• The villain CANNOT be petty or have a "rage" button--ever. They can have personal preferences and motivations, but trashing their goals for wasteful short-term (or worse, merely momentary) benefit just makes them look foolish.
• Just to expand on Vaalingrade's comment: have the villain genuinely, seriously LEARN and improve. Demonstrate that they're detail-oriented, and that they really do analyze, prepare, and re-evaluate.
• Give the villain other plans that the PCs can't really stop, but that they can still hear about. Stuff that's just beyond them to deal with. E.g. diplomacy with people WAY outside their league, or securing new resources, or producing clever new inventions/strategies, etc. Stuff that shows off their smarts without needing to go head-to-head against the PCs. You can also have him "win" in ways that end up coincidentally good for the PCs, that way the villain's victory doesn't feel like being defeated.
• If possible, do everything you can to try to have at least one Xanatos Gambit. TL;DR (to spare you from visiting TVTropes and losing hours of your life): the Xanatos Gambit is named after David Xanatos from the excellent animated series Gargoyles. Xanatos was infamous for being a magnificent bastard (probably the purest demonstration of that trope), and for being really, really, really good at making plans where literally NO MATTER WHAT happens, he benefits, sometimes more, sometimes less. If the gargoyles lose, boom, he's gotten a victory. If they win, he gets a different victory. This sort of thing is obviously very hard (otherwise it wouldn't be impressive!), but implementing it as much as you can will help a lot.

As a good example of a (small) Xanatos gambit from a game with a story I really like: There's an ancient antagonistic force who wants to set up a world-shaking catastrophe. Call him Steve. (The details aren't important--suffice it to say, he has understandable reasons to want this, and you empathize with his motives, but it's still an evil thing to do.) You as the main character have just recently foiled his group's plans, and left Steve as the only one of his group still fully in control. Instead of lashing out at you, however, he does something really really sneaky. See, you just saved the world and inspired a new group of heroes to follow in your footsteps. As part of doing that, you told people the true story about a noble person you really liked, call him Albert, who had been falsely slandered as the horrible monster who caused all the world's problems. (Truly, Albert and his friends DID cause those problems, but Steve's allies had deceived Albert into thinking it would save the world, not destroy it.)

So Steve, who is a powerful magic-user, possesses the (restored) corpse of Albert....and uses it to praise you and your work, and spread the word of your patron deity! He then uses trickery (illusions) to trigger the magical awakening that gives people the Special Protagonist Blessing like what you have, and starts encouraging every person he can to go off and help fix up their messed-up world. There's nothing you can do. If you speak out against Steve, you'll just sully all the work you've put into salvaging Albert's reputation. But you know Steve is up to something nefarious, that he's going to exploit this somehow. He's got you trapped; if you defeat him directly, you'll damage the world you JUST saved, and if you stay silent, he's free to do what he wants. THAT is (a small version of) a Xanatos Gambit. No matter what you do, Steve wins, at least this round.

But let me make up a different example here. Let's say there's a currently-running election for governor of a particular province. The election is hotly contested and small differences could make or break the outcome. The First Minister of the royal court is worried that this election is going to be tampered with or that some other kind of problem could occur, so (through intermediaries) they're asking the PCs to investigate. Turns out, yes, there IS vote-tampering going on, and a sleazy ultra-rich merchant is pulling the strings, seemingly trying to set up a favorable result for herself; we'll call her Joyce. However, the situation is much more complex than it appears, and there's essentially no result that won't benefit Joyce, because she's actually manipulating votes against her preferred candidate. Further, it turns out that the lieutenant of the guy she's manipulating votes toward is actually in her pocket, an extremely well-placed mole. And, finally, she is on good personal terms with the king, who respects her administrative and business acumen (and doesn't know about, or refuses to believe reports of, her unscrupulous deeds.) All of the following results in some way benefit her, though some more directly than others:

• Her favored candidate wins the race despite the vote manipulation, which is never revealed. An obvious win for her.
• Her favored candidate loses, but the election interference is immediately revealed, forcing a second run, and her favored candidate will have a major bias toward them because there's no suspicion of cheating.
• Her favored candidate loses, but she's able to leak the proof of vote manipulation. The election is tarnished, and the man himself forced to resign; his second-in-command takes over, and now she has a mole in a leadership position for their political faction, potentially establishing decades of beneficial results for her.
• Her favored candidate loses, a do-over election happens, and her favored candidate loses again. This is obviously not great for her, but she's sown the seeds of discontent with the existing system, which will make a proposal to abolish the (corrupt!) elected governorship and instead use an appointed governor much more palatable to the people--and since she has the king's ear, she herself will be one of the most likely people to get the job. Even if she doesn't, whoever does (or whoever works for them) can be bought. Etc.

As you can see, this requires a lot of forethought and planning, and doing everything you can to mitigate any weaknesses the plan might have. (In this case, the weakness is "the vote manipulation AND her mole are exposed and pinned on her specifically" is a remote but possible outcome, which would be Very Bad for her, essentially a total defeat.) Even if you can pull something like this off, try to be careful and judicious with it. If you do this too much, players may start to feel like you're unfairly ensuring that Steve always wins--that is, you aren't just coming up with fiendishly clever plans, but rather that you're railroading them into having Steve win all the time. A mixture of genuine failures (that your villain must learn from, as noted), Xanatos Gambits, and tangential (or helpful to the PCs) successes will do you much better.