That's why you call rolls for no reason, though.

I mostly disagree. It takes away a feeling of agency even if its still random at the end of the day. Just trust your players not to meta game. There are exceptions when it would be hard for the player to still get the intended experience when not meta gaming; but leaving the existence of that experience up to a roll in the first place is probably whats at fault.

Yeah, I love rolling dice, but certain rolls shouldn't be done by the players.

Rolling on a hit in combat? That should definitely be the player. You know how well you swing your sword and when it makes good contact.

Rolling on perception should almost always be done by the DM. This is especially true when another party member can rescue the bad roll. Like, someone rolls to spot a hidden enemy. They fail, but shouldn't know it, but they rolled a 2, so... Another player at the table sees this horrible roll and they have their character light a torch and look out into the wilderness. Sure, that's metagaming, but it's really hard to avoid when you know someone failed a potentially important roll.

One idea I'd like to see, and might try if I ever DM'd a game would be Dunning-Kruger rolls. The Dunning-Kruger effect is basically how people who are incompetent at something sometimes think they're much better than they are, and people who are experts (and realize how complex things are) underestimate their own competence.

So, in this case, the DM rolls a die which says whether the rolls are normal or reversed, then the player rolls. If the DM's roll said the player's roll was reversed, the player's 20 might become a 1, or a 1 might become a 20 (the actual number is 21 - roll). Mid rolls stay roughly the same: a 10 becomes an 11, for example.

If the barbarian is trying to check for traps and gets an 18, the DM might say "You're confident there are no traps", but that could be the result of overconfidence when they really "rolled" a 3. If they get a 10, the DM might say "You didn't notice a trap, but you're not sure". You could set this up so if someone has a proficiency, the DM rolls a D10 and only a 1 means the player's role is reversed. But, if the player is trying something they're not good at, a 1 to 5 on the D10 means it's reversed.

I haven't tried this, so there may be serious flaws in it in reality. But, I like the idea of players still being able to roll for something like spotting a hidden enemy, but not knowing for sure if their roll is good or not.

This is why you tell them sometimes the good result on a low roll.

Didn't old school D&D have the DM roll on the player's behalf?

The first (and pretty much only) time I played D&D I didn't know what "metagaming" was and accidentally thought about the puzzle as myself instead of as my player. Apparently the DM wanted justice and I ended up ruining the session for everyone. Needless to say I didn't go back out of guilt

Moral of the story: please try to be patient with your players. Not all of us are great at avoiding metagaming immediately :\

Honestly, perception checks should be rolled behind the screen. Or anything where the character wouldn't immediately know the outcome.

Sure, players shouldn't act on things their character doesn't know, but why give them the temptation?

Or do I?