The real problem with 24 is that each season they run out of steam. It usually starts out promising, but then, 8-10 episodes in, they start kind of bumbling around. It's usually after the payoff on the first big threat. It's also probably about how far ahead the writers had scripted. At that point the writers are just making things up as they go along. Sometimes it's clear they wrote themselves into a corner. Then some whole plot thread or character gets abandoned. 24 usually comes together again for the last few episodes. But the middle 10 are too often a rambling, incoherent mess.