Well it's what happens when the execs decide they need to 'change' things.
Definitely the reason the programming has gone down hill in several channels (Sci-fi to.. SHUDDER Sy-Fy.. was done to 'get out of the 'our viewers live in the basment' dynamic supposedly)
I think Firefly, The Tick, Futurama, Family Guy all suffered from Exec Meddling.
See for things like Anime, there are rules of cartoon animation set up during the mid to late 40's, and got expanded on in the 50's, which also got enforced at certain points and ignored at others. The major one is no death or blood. Also, the morality of the program has to fit within certain forms. Which most Japanese animations don't follow, not needing to, having different rules in Japan (The main one being that most Anime is not for children. It's aimed at ages between 14-24, depending on the theme. There are some kids anime, of course, but that doesn't end up as popular.) So to make it fit within the rules for Television (Which are so out of date, it's not funny) they have to cut out certain things.
Which is why ALL American channels butcher most popular anime. They HAVE to, otherwise it doesn't get aired, and they don't get the commercial revenue they want. And although they can let certain things slip, when it's as high profile as Anime, the networks HAVE to watch their steps.
As for Firefly et al. Not all of them were the fault of the 'execs' as everyone loves to blame. With Firefly for example, Joss Whedon lost interest with the series (Penning all of 2 or 3 episodes, and not directing a single one, if I remember correctly), but the fact that Fox bounced it's show time didn't help. Family Guy is a special case. Although the viewership was there, it was often played at the same time as Fraiser or Friends, or Survivor. So what people did was record the show to watch it later. So when people were polled about what they were watching at such and such a time, to the Networks it LOOKED like no one was watching it. Which now with the advent of DVRs and such, they old polling system needs to be reworked.
The issue with the Tick is that there is none. After three seasons, it did amazingly well for a Kid's Show. Lasting longer than most that aren't based on toys or other marketing gimmicks. And even then, some shows barely make it past one season.
As for Futurama, despite the fact that Fox hated the show, it lasted an amazing 4 seasons and spawned five movies, so this is another one that went about as well, or better than it should have.