Are there any actors/actresses who had the opportunity to leave a TV show on a high note but stuck around just long enough to see their characters ruined? If so, when should they have left?

Charlotte Rae on FOL. Once the girls were adults they didn't need a den mother. It was a show about female friends working together ala Designing Women.

Dinah Madoff on Empty Nest. Once her sisters left, she should've left too.

Charlotte Rae on FOL. Once the girls were adults they didn't need a den mother. It was a show about female friends working together ala Designing Women.
And that wasn’t even what the show was originally about in the first place. I was trying to see the point in the addition of Beverly Ann. The damage was already done and the girls were adults and late teenagers they didn’t need a chaperone.

Lucille Ball with the later “Lucy” shows. “The Lucy Show” was decent, but had a major decline during the second half of its run. “Here’s Lucy” was really subpar and that’s being kind. Lucy was trying to pretend she was still a young lady, despite that deep, froggy voice. Her kids were pretty awful on the show (Lucie has greatly improved since then). Lucy herself was reading off cue cards by then and her marvelous comic timing was gone. And the episodes either focused on Gale Gordon yelling at her, or some has-been guest star appearing and Lucy causing trouble for them. Very tired.

Jackie Gleason also falls into this camp. His later Honeymooners skits - as part of his variety hour or standalone specials - are embarrassing.

Lucille Ball with the later “Lucy” shows. “The Lucy Show” was decent, but had a major decline during the second half of its run. “Here’s Lucy” was really subpar and that’s being kind. Lucy was trying to pretend she was still a young lady, despite that deep, froggy voice. Her kids were pretty awful on the show (Lucie has greatly improved since then). Lucy herself was reading off cue cards by then and her marvelous comic timing was gone. And the episodes either focused on Gale Gordon yelling at her, or some has-been guest star appearing and Lucy causing trouble for them. Very tired.


Did you ever watch Life With Lucy?

Yeah Lucille Ball was the first person who came to my mind, that Life With Lucy show in the 80s was awful.

I think people are missing the point of the OP's post. They're not talking about people who should've retired but actors whose characters started out decently and either ran their course or outlasted their usefulness because the actors stayed on too long.

The first thing that came to mind was any child or teen actor who outgrew their roles. For example, Christina Applegate and David Faustino should've definitely bailed a few years before Married with Children ended. They were getting way too old to play their characters, especially Applegate, who I felt embarrassed for towards the end because the writers didn't seem to know what to do with the Kelly Bundy character anymore now that she was looking too mature and dignified to play her. (Larry Storch school of acting???)

Other child stars in this category are both the Greenbush sisters and Matthew Labyorteaux of Little House on the Prairie. With Labyorteaux, I've never seen a more promising character take such a major dive the way his did on the show--from cute, adorable rapscallion to baby murderer and drug addict. (I guess because he was beginning to lose his looks as he aged and the writers became disenchanted with him?) The Greenbush twins were just a waste of celluloid and should've left the show as soon as they could talk. Now everyone keeps asking if Carrie Ingalls was mentally challenged.

Yeah, I did see “Life With Lucy,” and it was sad. I’m not saying Lucille Ball should have retired. She just should have retired the “Lucy” character back in the 60s. I thought she was great in “Yours, Mine, and Ours” and should have done a series where she played a character more like that.

Would Potsie (https://en.wikipedia.org/wiki/Potsie_Weber)/Anson Williams on Happy Days count? He seemed to outlive his usefulness when Richie and Ralph left and Fonzie officially became the main character and Joanie and Chachi started getting more of the spotlight themselves. Potsie wasn't even featured in the series finale (https://ultimateclassicrock.com/happy-days-series-finale/).

Andy Dick on NewsRadio. His schtick got old by season four and without Phil hartman to bounce off of he was unbearable.

i know serval
josh saviano's paul pfeiffer
Jaleel White aka Steve Steve Urkel form family matters
screech form saved by the bell
George reeves form superman
adam west batman
gary coleman arnold jackson form different strokes

Andy Dick on NewsRadio. His schtick got old by season four and without Phil hartman to bounce off of he was unbearable.

Andy Dick usually is unbearable. Athough there's an episode of Star Trek: Voyager he guest starred in where he dials it down and is all right in. But his character of another EMH (Emergency Medical Hologram) is still used mostly for humor.

Ed.

In some cases, staying for a sixth, then seventh season and beyond can be very lucrative, especially for older actors. No guarantee that anything else will be as successful.

But often then, that show becomes less and less popular.

I was thinking about Staci Keanan from My Two Dads who later was cast in Step By Step. Maybe she had potential beyond tv in some movies, but Step By Step didn't really improve enough, and any acting potential she might have had as an adult actor wasn't going to be realized from Step By Step.

According to wikipedia, she left acting, and studied to become a lawyer and is now a deputy district attorney now, so maybe it worked out for her in the end anyways.