Easy way to look at this is to compare to all the alternatives. Are we going to fold to a min raise here... no. Should we call? Its not a good idea to flat call here with a shallow stack and mostly either fold on every flop if we miss or we have to just go with the hand and call down... which we could have then just jammed pre. Plus over calling lets in those players behind us and now we play multi way often. 3 betting to an amount other than all in would mean we put at least 1/3rd our stack in pre and are committed anyway. Looking at the alternatives they are all bad so it points to a jam.
Often when jamming you will get folds here and pick up blinds and at times will get called in flips (which is fine from out perspective with only 20 BBs). This time you just happened to run into one of the few
hands you did not want to see. Jamming is correct
