The Great Gazoo or whatever that annoying Martian was called on the Flintstones.
I recall that there were also several useless additions to the “Facts of Life” cast in later seasons.
And I’d just like to point out that the plural of “Ingalls” is “Ingallses.” A lot of kids came to live with the Ingallses.
[another hijack]He even has a one man show based on his character.
I exchanged some e-mails for a while with Alison/Nellie; she is a super cool and very funny individual who has more or less left show business save for an occasional stand-up gig. I love the faq section on her web-site.[/another hijack]
Well, of course Scrappy.
But dosen’t anybody remember when the Smurfs got to be all about the kid Smurfs? Man, did that ever suck.
Also, Olivia on the Cosby Show was an awfully obvious “kids getting too old!” ploy. Blech.
I disliked Dr. Katherine Pulaski, of Star Trek: The Next Generation. Although I’m keen on Diana Muldaur, I didn’t like the character that she played. I was very relieved when Gates McFadden returned to the show as Dr. Beverly Crusher.
Muldaur later had a great (but brief) role on L.A. Law which ended with her character falling down an elevator shaft.
Some actors just don’t have any luck.
Scrappy Doo
Gazoo
Cousin Oliver (and every single new little child they put in a show because the original little kids have grown up)
Deep Space Nine: Worf (great character in TNG, boring character here), Worf’s son (annoying-but-rarely-seen character in TNG, even more annoying, rapidly aged character here) and Ezri Dax didn’t do much for me.
Angel: Lorne was great as a recurring character for seasons 2 - 4. As a regular in season 5, he was pretty much useless. Same goes for Spike - great in “Buffy”, took away valuable airtime from longtime regulars on “Angel.” (And let’s not get started on Conner, another rapidly-aged character.)
Didn’t Scooby Doo have a cousin called “Scooby Dumm”? I would even go out on a limb and state that he was a worse addition than Scrappy, except that he seems not to be well remembered.
And not that it was ever a great show to begin with, but Buck Rogers really blew when they had Buck exploring space in an “Enterprise” like ship with a Spock-like sidekick “Hawk” and a second robot - Chricton, IIRC - that acted like a metallic Dr. Smith from “Lost in Space.”
Yep, but since he was only an occasional guest star, not a major character, he didn’t have the annoyance that Scrappy brought to the table.
By the way, they also had a female cousin named Scooby Dee. And, Scooby’s sister (Scrappy’s mother) was named Ruby Doo.
Really scary that I know all this.
[last hijack, I promise]Thanks for the links. I couldn’t remember Doc’s name for the life of me and, as usual, I’m too lazy to search.
Alison is adorable. Loved her site. I didn’t get to see her when she was here, or any of the other actors, for that matter. When you live so close to these things, you tend to stay away. Dean Butler was here again recently filming for some documentary or something he’s working on.
We need to start a Little House thread sometime, I think! [/last hijack, I promise]
Hate to say it, but Alan Shore on The Practice. I admit that James Spader was everything Dylan McDermott should have been, but the last season was like watching two different shows that clash in the night.
Also, we don’t have to see Mr. Whittingdale in the last few years of The Jeffersons, especially if he comes off like a fifth-rate Donald Trump.
Also, all the Doctor Who’s companions after his daughter Susan were less than worthless, except maybe Deena and Mary Jane.
Gazoo wasn’t that bad; he was supposed to be the prehistoric version of Popeye’s Jeep. In fact, Gazoo would have been better off being The Jeep, so that we can have a recurring character hopping onto different shows, just like Richard Beltzer’s Munch.
I would say Kelly and Paul on Cheers later seasons. Kelly was painful to watch, I can understand they felt Woody needed a girl but please. And I don’t know why they needed another Cliff Clavin.
Cousin Oliver is really lame
Cousing Oliver should take the blame
And I would rather watch anyone else
than this kid.
Pam on the Cosby show.
I also didn’t like Worf on DS9.
When Ron Ely replaced Keith Larsen on “The Aquanauts,” as I’m sure you all agree. 
Also, when Peter Graves joined Mission: Impossible. I couldn’t watch it after that. Graves just wasn’t right as the leader of the IMF. 
He also showed up for his marriage to Hot Lips. Hawkeye and BJ got him drunk, and put him in a full body cast.
You mean Crappy Doodoo :wally
Poochie.
Duh.
That was about time the Smurfs started time-traveling, wasn’t it? Truly the death throes of a classic cartoon.
The red-headed DA on Law and Order.
Donofrio’s new sidekick in Criminal Intent.
The actor who took over as Sully’s partner in the X-Files when Duchovny went “part-time.”
All the new male doctors on ER.
Does Jar Jar Binks qualify?
I never liked Dwight on Futurama. I realize that was the whole point, having a Wesly Crusher-like character that the other characters hated too, but the gimmick wasn’t funny enough to overcome the annoyingness.