Let's take "The Big Bang Theory," arguably Lorre's biggest hit, as a prime example of this issue.
Pretty much every character in this sitcom is, to put it lightly, a crappy person (particularly in regard to how male character treat female ones, which might be the show's biggest issue altogether). As the series continues, it seems bizarre that any of these people would stay friends based on how they treat one another. Sheldon (Jim Parsons) is, perhaps, the worst of them all — he seems to have nothing but contempt for his friends and loved ones, all of whom he views as utterly beneath him. Sure, he says nice stuff in the series finale. That's after 12 seasons of treating his chosen family horribly.
"Two and a Half Men," which focuses on Charlie Sheen's "hedonist" main character, is similarly odious, although the characters don't just insult each other: they're equal opportunity offenders and attack anyone who's different from them. Even the way Sheen was written off the show after he went completely off the rails in real life was unnecessarily over-the-top. In the series finale, though people believe Sheen's character (also named Charlie) had been dead for years, he nearly resurfaces only to be crushed by a falling piano. To really drive the point home that Charlie Sheen sucks, Lorre appears on-screen in a director's chair and says one of Sheen's real-life catchphrases, "Winning." Okay, Chuck. We get it, man. Just say he moved to Mongolia or something. This is embarrassing.