For the most overused word in pool, I'll offer "should" as in:
1) I "should" have made that shot
2) I "should" have run out
3) I "should" have won that match
After skids or balls rolling off or freakishly bad luck, I guess such a comment can be dealt with, but these comments tend to be heard after one has failed due to poor execution.
As a late teen, I used to often practice with a top pro named Jack Colavita. I recall that if I said "I should have made that shot" to him, he would typically reply "no you shouldn't have, not when you hit it that bad." Now, I'll have to admit that at first this comment rubbed me the wrong way, but it finally dawned on me that he was right.
After making a poor stroke, why on earth would one feel they should have made the shot? Constrastingly, after failing, one might say "I expected to make that shot" and be within the boundaries of logic, as this refers to the moments prior to the stroke. The thing is, with rare exception, nobody partcularly cares what your expectations were, so it's best to remain silent.
If you failed due to poor execution, you "should" have failed.