I wouldn't call Fighting Foodons a failure. It actually outperformed Kirby and Ultimate Muscle, the only two shows Fox Box kept from the original batch.
Cubix failed on Fox Box for the same reason Stargate failed: The crappy 8 AM timeslot. Interestingly enough, (Stargate is getting HIGHER ratings in syndication than it ever did on Fox Box.) Every show in that slot, from Yugi-oh, to Jackie Chan Adventures, to Scooby Doo, to Rugrats, ultimately fails, probably because the kids aren't up yet in the Eastern Time Zone, and they CERTAINLY aren't awake in the Central Time Zone.