Five Titans, five seasons, but Starfire got none. Season 5 was her turn but instead it was Beast Boy's second season. Subsequently her archenemy is the only archnemesis to not be main villain of a season (Slade got two seasons, second being Beast Boy's first season).
She's my favorite Titan so that's one of the few things I dislike about it.
So why in the name of Sephiroth did they single her out in this way? Is it because of how powerful she is? I heard someone say writers dislike really powerful characters or something.