How to express happiness on someone's failure? [duplicate]
Solution 1:
The word you're looking for might be:
Schadenfreude
Definition by Merriam-Webster:
enjoyment obtained from the troubles of others
Definition by dirctionary.com:
noun
- satisfaction or pleasure felt at someone else's misfortune.
Solution 2:
While it does not name the emotion itself, a common saying in this sort of circumstance is good riddance. "Riddance" means (OED)
A deliverance or relief which consists in getting rid of something. Frequently with modifying adjective, as good, happy, etc.
In context:
S. Rushdie, Satanic Verses i. iv. 79: "He was glad to have seen the back of his badly behaved colleagues; good riddance to bad rubbish, he thought."
The extended phrase good riddance to bad rubbish is also in frequent usage, though my impression is that it is more common in British English than in American English. Someone who says "good riddance" upon learning that they are rid of something is very obviously happy that it is gone.
Solution 3:
If your joy is derived in large part from being right about thinking that it would be a failure, I might go with vindicated:
vindicate VERB
1 Clear (someone) of blame or suspicion.
1.1 Show or prove to be right, reasonable, or justified. 'more sober views were vindicated by events'
It's that later definition which you're invoking. You had a point of view (that StackOverflow shouldn't be doing documentation). However, other people didn't necessarily agree with your point of view. Now that it has failed, you are happy that your original prediction turned out to be correct. As such, you were shown to be right, reasonable and justified in your beliefs and predictions, and thus were vindicated.
While not directly an emotion word (it doesn't strictly speaking have anything to do with happiness), the feeling of happiness at being proved right is universal enough that the word "vindication" carries with it a positive connotation. A native English speaker, when hearing "I felt vindicated when StackOverflow Documentation failed", would understand it to mean that you were happy at StackOverflow Documentation's failure.
Solution 4:
I like Gratifying.
Gratifying: giving pleasure or satisfaction. [Webster's]
Gratifying is nice because it has the potential for negative connotations.
(positive) My promotion was gratifying because I worked really hard for it.
(negative) Watching the bully fall down the stairs was totally gratifying.
Solution 5:
I expect that you are feeling relief with the decision, which one can argue is not relief because of some failure, but rather relief in response to a successful return to core principles.
relief
NOUN [mass noun]
1 A feeling of reassurance and relaxation following release from anxiety or distress.
‘much to her relief, she saw the door open’