When you say that JJ is a bad hand, you must always keep in mind that in actual fact JJ > 1010 > 22, and JJ should be a hand which you value fairly highly. However, you must also bear in mind that it is not a monster, and if you face raises and reraises and shoves then it's not a case of going for it no matter what with JJ. It is a good hand, but it's not so good that you can never fold. Think about the
odds you're getting compared to your opponents ranges in any of these spots. Quite often there might be a spot where you feel you have to call with JJ when in actual fact your opponents range might look like JJ-KK,AK, sometimes AA, which you are clearly crushed by. Think logically before you call a shove after a lot of raises for 30BB.
JJ are fairly awkward postflop, but I don't mind them too much. Sometimes they are an overpair, sometimes they are a set, sometimes you get an overcard and you're going to need to try to get to showdown rather than continuing to bet and raise. Out of position the hand is admittedly quite sucky with overcards, but as long as you are relatively confident of your opponents range you should be able to make sensible plays with it, as with any hand.
My least favorite hand is 22 by the way, really bad hand in tournaments. You can't invest a large amount of your stack with it preflop without having to go all in or fold, it flops absolutely nothing most of the time, it doesn't have the straight potential of other pairs, and you have to get it in and sometimes even call shoves if the price is right with it but you are almost always flipping or behind. Guess I need a thread on that