Hey, quick question. What do you guys thing passive perception is and how best to use it in a game?
The reason I'm asking is that I had several instances in the past where a player argued their pp should have compensated for their negligence. For example I had a scenario where one player didn't bother to check and activated a pit trap. The following argument was something among the lines of "seriously and my character didn't notice the trap despite their high pp?". similarly, last game the passage forward was blocked by a wall of force, which could be deactivated by placing a gem they found before in a hidden keyhole in the wall next to it. Again, my players (different group btw) only focused at the force wall itself, trying to smash trough it, see if certain things could pass through ect, but didn't bother to do anything with the surrounding area. They didn't even bother to roll an investigation or anything. So, when I finally had an NPC point the keyhole out to them, because they were utterly stuck otherwise, once again the complaint came "but my passive perception...."
Thing is, I don't really see it that way. I don't agree with the idea of a character's pp being used to excuse the players from having to use their brain. The way it was explained to me, and the way I'm using pp, is mostly to set up things behind the scenes without having the party necessarily be spoiled about what's happening. For example, a creature tries to stealth up on them. Then their pp would determine if they spot it before it can get the jump on them or not.
But yeah, that's my general opinon on that matter.
What's your guys opinion on it? Am I using the stat wrong? Should it be allowed to justify players just knowing about things without even paying attention to anything?
Thanks for reading and thanks for your time regardless. I wish you all the best of days^^

Edit: To clarify a bit, as to why I don't agree with the idea, it's because; let's say you have a WIS based character in your party. Take my current group for example, who has a monk with a pp of 18 at level 5. Usually most DCs at that level are somewhere around 13-18, based on how difficult they are. That would mean they would be able to immediately spot any and all traps and/or hidden mechanism/ monster, as well as pretty much anything else, the moment they step foot inside a room, making the very concept of having traps or secrets in the first place completely meaninglessness. At that point why even bother having traps or hidden areas and not just simply give everything to the players once they step inside a room? It would really just amount to the same thing.

Problem is that players can't actively see what's in a room. They only 'see' what you describe to them.

Obviously you can't describe absolutely everything to them, even the things that are hidden, because it makes things trivial. But you also don't want to get into the grind of every single room starting with "we search every inch of the room for anything" and rolling for investigation. Snooze-tastic.

Passive perception allows the DM to decide what the players notice, and what they don't notice. You decide the DC to notice your traps, and if the player's PP is higher, they notice something awry when they walk into the vicinity. It doesn't need to be a full description of the actual trap and all its details. It could be one flag stone that doesn't have any footprints in the dust, because the denizons of the dungeon know to avoid it. It could be a tripwire and holes in the wall. PCs still need to identify and disarm the trap. Things can also be really well hidden - "you didn't notice because it's very well concealed" is a valid response. It just shouldn't always be the response.

Think about real life - when you walk into a room, do you need to search the room to notice things? Or are there some things you just take in? Does everyone take in the same amount of information in a glance, or do some people have a keener eye than others that gives them more information? Does Sherlock Holmes notice the same details in a room as Derek Zoolander?

By not running PP I feel you are blunting the value add of characters with higher perception.

Quote from frostfoxfive >>

Hey, quick question. What do you guys thing passive perception is and how best to use it in a game?....

Edit: To clarify a bit, as to why I don't agree with the idea, it's because; let's say you have a WIS based character in your party. Take my current group for example, who has a monk with a pp of 18 at level 5. Usually most DCs at that level are somewhere around 13-18, based on how difficult they are. That would mean they would be able to immediately spot any and all traps and/or hidden mechanism/ monster, as well as pretty much anything else, the moment they step foot inside a room, making the very concept of having traps or secrets in the first place completely meaninglessness. At that point why even bother having traps or hidden areas and not just simply give everything to the players once they step inside a room? It would really just amount to the same thing.

  It always on and is an automatic give me.  But with your gem/force thing, I would have set the PP 5 higher than normal. 

I think of passive perception as being you ability to notice things without actively looking for them. I am also of the opinion that it should fluctuate a bit, but to do this it's easier to just change the DC a bit depending on the situation:

In your first case, if the players were simply traveling from point A to point B, then the DC is low for the pit trap because they can be assumed to be wary, looking around and likely to notice these things without having to roll for it each time. so your high PP PC would see the trap.

Now, if they are doing something else - charging at an enemy, trying to get to the end of a corridor before a door closes, performing a concentration spell, running, charging at an enemy - that's when I would make the DC higher to see the trap. Just look at people trying to text & walk - they walk off piers, into lamp-posts, into traffic... now imagine them performing less consuming tasks, but where the lamp-posts take swings at them, the traffic is disguised as a woodland walk, and the ends of piers jump out from behind trees to stab them. A rogue trying to pick a lock will face higher DC passive-perception checks (for me) than if they were stood in a room looking around.

I certainly think that Passive Perception is important, and players having a high PP is not to be seen as a bad thing. For example, if the rogue has PP 25, but the paladin goes first and doesn't see the trap, you can't say that the rogue should have warned them - they should instead have waited for the rogue.

Passive Perception sets a floor for what is obviously perceptible to the senses for that character. If their Passive Perception is higher than the difficulty to notice something they should notice it as soon as it comes into range of any of one of their appropriate senses, without having to ask to look for it. This doesn't tell them what anything means, mind you. That's the job of Investigation. Perception just gives sensory information.

Likewise, Passive Investigation sets a floor for obvious meanings of things. If their Passive Investigation is higher than the difficulty to interpret something the meaning should jump out at them immediately without them having to ask. A character with a high Passive Investigation is someone who can look around a room and Sherlock Holmes the place, reading clues and traces like a book.

Passive perception applies to tasks done repeatedly OR when the DM wants to resolve a situation without the players rolling dice.

The PLAYER is being passive NOT the character. A character who is doing something else doesn't even have a passive perception. For example, if a character is busy mapping the dungeon as the party moves along then they are NOT paying attention to their surroundings and passive perception does not apply.

PHB p183 "Characters who turn their attention to other tasks as the group travels are not focused on watching for danger. These characters don't contribute their passive Wisdom (Perception) scores to the group's chance of noticing hidden threats."

PHB 175 "A passive check is a special kind of ability check that doesn't involve any die rolls. Such a check can represent the average result for a task done repeatedly, such as searching for secret doors over and over again, or can be used when the DM wants to secretly determine whether the characters succeed at something without rolling dice, such as noticing a hidden monster."

It is a very common misconception that a passive check is when the CHARACTER is being passive ... the character is doing nothing ... that isn't correct. If the character is not taking an appropriate action then passive scores don't apply.

Example from Lost Mines of Phandelver:

"About 10 minutes after heading down the trail, a party on the path encounters a hidden snare. If the characters are searching for traps, the character in the lead spots the trap automatically if his or her passive Wisdom (Perception) score is 12 or higher. Otherwise, the character must succeed on a DC 12 Wisdom (Perception) check to notice the trap."

If the characters are actively searching as they move along then their passive score can be used to find the trap - if they are NOT searching (ie not paying attention) then they need to roll.

Examples:

- A hidden drawer in the desk but the player says they are searching the walls. An investigation check, passive or active, is NOT going to reveal the hidden drawer because the character is not looking in the right place.

- However, if a character enters a room and says, I take a close look around the room, then instead of having the character roll 3 checks for each wall, they can check the character's passive perception to see if it is high enough to notice the secret door. If it is the DM just narrates the character being particularly perceptive and noticing the secret door. If the passive is not high enough the DM could ask the players to make a die roll to resolve whether they notice whatever is hidden.

The same goes for all passive skills - they are for tasks done repeatedly or when the DM wants to avoid rolling dice. If the character is NOT doing the task repeatedly (i.e. looking around in the relevant area) then they can't succeed on a passive check.

In your example of the keyhole by the force door where no one looked at the walls, there are several options.

1) If the character specifically never takes a close look at the walls then they will never notice the hidden keyhole. Since they aren't looking they can't see it. On the other hand, if the player says they look at the walls then if their passive perception is high enough they will notice the keyhole. However, this can lead to a confrontational playstyle where the players will specifically state that they are looking at everything as soon as they realize that the DM wants to know exactly what they are looking at.

2) Based on the situation, the DM could assume that the character is always looking around at the obvious surfaces so if there is something to notice then they will usually notice it. In this case, you would check the passive perception and if it is high enough then just narrate what is found.

3) If the character needs to specifically look at something but doesn't you can still make it work by giving them disadvantage on the passive check. Disadvantage on a passive check decreases the passive score by 5. So an 18PP becomes a 13. If this is enough then you can still just narrate them finding the keyhole. If not, then they will need to examine the side walls.

4) If none of the passives are high enough then you'd ask for an active check.

However, as a DM, you need to pay attention to exactly what the players are saying, someone is likely to say that they just "look around" which will include the walls and other areas.

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As for high passive perception characters - yes they notice a lot and that is OK. They have invested resources into being able to notice things usually at the expense of other abilities. I have a rogue with a passive perception of 28 and a passive investigation of 29. They do not miss much but traps aren't usually that big a focus in the game since the kind that can be detected and disabled by skill checks generally aren't that much fun anyway.  (P.S. The numbers come from Rogue - level 17 - expertise in investigation and perception +12 - Observant feat +5, 12 wis  +1 and 14 int +2 - however, even at level 1 their passive perception was 20).

I just use Passive Perception as a floor for Perception Checks for ambushes or to detect traps. If the party are about to ambushed by enemies who roll higher stealth than the highest players passive perception, I ask for a perception roll from everyone. 

Of course if a party member is following a map or footprints, then they can't use their passive perception as their attention is elsewhere.

I interpret passive scores as basically equivalent to taking 10, so if you're walking at a normal pace it will spot anything where the DC is low enough and I would otherwise allow a check to notice as a free action. If you're traveling at a slow careful pace, equivalent to spending your action every turn on rolling perception, it will spot anything where the DC is low enough and I would allow spotting it with a standard action.

Also, you can only perceive what you can see.  So if the trap doesn’t have any visual clues on the side facing the players, no amount of passive perception will help.  Now, some digging around with a pole or some heavy barrels, or an investigation check might work…