Originally Posted by RagnarokCzD
Unspecified ... and not relevant, all that failed check is telling us is that he noticed you ... everything beyond that is matter of roleplay interpretation. wink

Originally Posted by Zellin
Passive perception for starters. And passive perseption is already 10+Perception skill value. So if the opponent managed to go down to 5 with his passive perception he is effectively deaf and blind.
That is once aggain just roleplay interpretation ...
All that number tels us is how hard it will be to slip around him ... he can aswell be just ignorant, distracted, focused on sonething else, or simply sleeping (even if on duty) ... but even as such he cant ignore obvious threat. smile

Stealth just shouldnt equal "being undetectable by any means" ... and if (and that alone is a HUGE if ... its not even "a" ... its THE huge if ... thats how huge it is) it should mean "being undetectable by any means" ... there simply shouldnt be any check in the first place, since its effectively pointless.
Once again: go get more familiar with the system. Nothing here is just roleplay interpetation. Numbers in D&D do have their interpretation by the book. You get -5 to passive checks when you have disadvantage. Guess what gives disadvantage on perception checks? Being deaf and/or blind! We here are forced to work with both at once since the game doesn't really work with hearing.
And no one says here that steath should be undetectable by any means. I'm among those who insisted that stealth shouldn't be just walking around those vision cones and hearing should exist. But you lost the point that stealth already opposed by 10+Perception of the opponent. Most of our opponents will have 10 and even more for us to roll against. Even if they are distracted, because that's what passive perception is, it's how good you notice things around you when you're not intentionally paying attention to them. If we remove auto fail on 1 for stealth check we still will fail, when rolling 1 in most cases. So you can just leave stealth out of this conversation entirely, it won't win anything from removed auto-fail in normal situations, we just won't auto-faill to stealth against deaf and blind anymore. You may say that said deaf and blind could get some compensatory feeling of environment, but that would mean that he has some points in perception and his passive perception goes above 5 and we once again get a good chance to fail against him.
There is no such thing as just numbers D&D, they have meaning and rules for going up and down. Larian here simply broke one of those rules and throw away the meaning that way.