How I Met Your Mother was so bad they released an alternate version where the mother lived on the DVD.
So they torpedoed Robin and Barney just so she would run back to Ted?
Cool, cool. "She doesn’t want kids, he absolutely does” was just a minor footnote. Am I missing something? Or did they just want their own bargain-bin Ross and Rachel?
The Mentalist, after 5 and a half seasons of hunting Red John, he's finally revealed and defeated and it just keeps going for another season with a mostly new crew and it tries to get you hyped for new villains but nothing measures up to Red John, it just goes out with a whimper not a bang. it should have ended with Jane killing Red John but instead the execs thought they could keep milking the series, turns out no they couldn't
The Red John reveal never sat right with me. Mostly because it was the same twist as
Profiler—the killer’s just a random small-town sheriff, first time played by Dennis Christopher. If you’re going to recycle a plot twist, maybe don’t steal one that wasn’t great to begin with.
Battlestar Galactica was another one with a dogshit ending
Having devoured 11 seasons of these damned things—all of DS9 and most of
Battlestar Galactica too—I always came away baffled by the clunky, half-baked religious allegories. Then I found out Ron Moore’s Catholic. Suddenly, everything made unfortunate sense.
It's not the actual finale, but the finale of Babylon 5 Season 4, which was supposed to be the series finale before they got S5 greenlit, was embarrassingly bad.
Hope no one minds me barging in to talk about Babylon 5, because honestly, I don’t get many chances.

First, the disclaimer: I liked the show overall, but it often tried way too hard to be clever with all the time-travel nonsense and flash-forwards that felt like they were just jerking off.
Season 4 was supposed to be stretched over two seasons, but when cancellation loomed, they crammed everything in like it was the last shuttle off Earth. Result? Sheridan sees the Centauri war in the future… then acts completely shocked when it actually happens. Because acknowledging that time travel ep would've made season 5 completely pointless. So they just ignored it.
Londo and G'kar had reached their apex, and by season five, the show was scraping the barrel, desperately trying to repackage their blood-feud as an odd couple comedy. Yes, the chemistry was undeniable, but after everything that happened, the most they could ever credibly offer each other was a curt nod. Friendship? Never. Not in this life or the next.
And then there’s the Telepath War, which exists solely to hype a spin-off that never happened or to sell some tie-in novels no one read. It added nothing and went nowhere.
That said, it's not the disaster people claim. There were some great performances in season 5. Especially the ghostly cameos in "Day of the Dead."