You ask the key question that radiofans outside the business don't. They don't even
think of that question, because to their mindset, "successful" means "played the music I wanted to hear".
Unless our friend
@Dan Gorby can show us some experience in the business -- which I sincerely doubt, since he's been here for over ten years and has posted a total of nine times ... none of the pros can restrain themselves to less than one post per year -- I have to presume he has that mindset and definition.
He is, of course, welcome to rebut me with facts about the station's commercial viability, including whether or not that was a factor in its demise in 2020, provided he has access to any such facts.