Here's some more:
Spider-Man Unlimited & Avengers: United They Stand (1999): Fox, or more specifically, Saban, fumbled big time with these two. With the Avengers, Saban decided that certain of the characters (Ant-Man & Wasp stand out) should have full-face helmets, a la the Power Rangers & Beetleborgs. That was the kiss of death all by itself. Spider-Man Unlimited sent Spidey to Counter-Earth, but the complex plot was lost on fans expecting a more natural follow-up to the last series. Fox suits, desperate to counter-program the hottest show of the period (Pokemon), pulled SMU after 3 weeks. Avengers was delayed, then pulled, all within about a month.
Wishkid, Pro-Stars, & Hammerman (1991): DIC's unholy trinity of celebrity-driven toons. Two of the three aired on NBC, back-to-back, even. Hammerman was bounced around by ABC, which knew it had a turkey on its hands. Of the three, only one had the actual star-inspiration voicing his animated likeness, and that was Macaulay Culkin (Wishkid). MC Hammer did some wraparounds and the theme song for Hammerman, but the concept just died because the titular hero's powers come from a pair of shoes. Oh, stop the pain! Pro-Stars gave us Bo Jackson, Wayne Gretzky, & Michael Jordan, but none of these star athletes actually contributed to the show, aside from the clips used in the show open. I get the concept, but the execution was about as bad as, say, the weak sisters of the NBA and/or NHL.
Skeleton Warriors & WildC.A.T.S. (1994): These two fell victim to what I call "late-start syndrome". Delayed two weeks for reasons known only to the network (CBS), despite much hype. Shoot, the "Adventures" comic Image put out for the WildC.A.T.S. series came out before the TV show launched. As memory serves, these two were to debut the week after the US Open Tennis tournament, as per CBS tradition. Didn't happen. I watched the first two WildC.A.T.S. eps, and that was it. Had it started on time (Nelvana has a better track record, doesn't it?), maybe it gets renewed. Same with the Skeleton Warriors (though I didn't follow the show).