@mikemearls @Asmogorgon @ChrisPerkinsDnD @JeremyECrawford @MikeMercer Sorry – when do you use Passive Perception instead of rolls?
— Bryce Walton (@BryceWalton) October 28, 2016
A DM uses passive Perception when you might notice something but aren't actively searching. If you search, you make a check. #DnD https://t.co/9QhN7mM007
— Jeremy Crawford (@JeremyECrawford) October 28, 2016
That is not even the rule he wrote. Pg. 175 of PHB. “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”