First off there are those caches where you feel a bit more effort could have gone in and they are somehow deficient(28). There is even one cache called Nude up for a Smiley, which could make you feel sexy(6), but most of the time and most caches make you feel happy(52)
Possibly, however a very few will make unhappy(123) and on the odd occasion some caches make everything perfect(1). And of course there are puzzles like this one that are downright evil(117).
FTF was Cankid