Timeline for What does a player learn when their spell fails for a hidden reason?

7 events

when toggle format	what		by	license	comment
Jun 24 at 7:38	vote	accept	Matthieu
Jun 14 at 4:26	comment	added	Nobody the Hobgoblin		@VSZ I like to consider narrative cohesion over strict RAW too, so no objection to the comment. The asker however states they prefer a RAW answer, so this answer is focused on what RAW is.
Jun 14 at 4:23	comment	added	vsz		Sometimes it might be better not to blindly follow RAW and flesh it out a little more. For example, if a spell has a reflex saving throw, then the target is basically dodging the spell on a successful save, so the DM should describe that dodging, if it's visible for the player characters. If it's a will save, then for a high-level boss you might not perceive anything, especially if the boss could have saved even on a very low roll. However, a lesser enemy barely making a will save with a high roll could be described as having to focus really hard to withstand the mental toll of the spell.
Jun 13 at 20:19	history	edited	Nobody the Hobgoblin	CC BY-SA 4.0	added 6 characters in body
Jun 13 at 6:30	history	edited	Nobody the Hobgoblin	CC BY-SA 4.0	added 3 characters in body
Jun 13 at 6:23	history	edited	Nobody the Hobgoblin	CC BY-SA 4.0	added 506 characters in body
Jun 13 at 6:12	history	answered	Nobody the Hobgoblin	CC BY-SA 4.0