I agreed to let him join us, even though it was 'against my better judgment'. [=even though I did not think it was the best thing to do]
In my 'judgment' [='opinion'], the stock has performed badly. = It is my 'judgment' that the stock has performed badly.
“Were his policies good or bad?” “I'll have to 'reserve/suspend judgment on' that. It's too soon to know.”
(..) Aaah! Sorry! So what now, Jack Sparrow? Are we to be two immortals locked in an epic battle until judgment day and trumpets sound? Or you could surrender. Aaaah! All of you with me! Will is in that cave. (..)2003 Pirates of the Caribbean: The Curse of the Black Pearl