Ben's like a reverse King Midas, everything he touches turns to crap.
If he's not screwing up with a criminal lack of common sense, he was just plain cowardly, e.g. abandoning Clementine when he was armed... and who had the lapse in judgement to even give the kid a gun I have no idea.
Trading with the bandits was just plain stupid considering Jolene gave us the story about what happened when she "begged them every way she could" for her daughter and we know how that turned out. Oh yeah, the people known for little things like rape and murder are surely going to be above lying.
And pulling the hatchet out of the door that's covered top to bottom in blood? Really? This shouldn't require any sort of explanation. It didn't occur to him to atleast ask "hey, this seems kinda strange, is this maybe important?".
He's had his three swings, and they were all strikes. He causes, or contributes to the deaths of no less than three people (And no, I'm not counting Carley/Doug) and abandoned Clem to be eaten alive. The only redeeming quality he had is that he finally understood he was dead weight the group shouldn't have to pull.