even if u are sure that hitting one of your overcards would win u the pot, the odds of u doing so are only 13.2% (on a card-by-card basis).
If you have 2 overcards you have 6 outs, which is ~24% to hit at the turn or the river (1-(41/47)*(40/46)).

JT is too weak even if I do hit my pair, because I dont have a good enough kicker, but higher overcards (Ak, AQ for example) it may be worth it to call if you get the pot odds