I have to respectfully disagree with Jessi10. In my humble opinion, being successful on Hubpages has got nothing to do with money, business or how much you earn with it.
If making a descent living from Hubpages is the only measure to success, lots of writers can take their bags and leave.
They don't because most of us writers are here to create. To be part of a community that supports and comments on their work, so we can grow as a writer and feel enriched as a person.
Money is just the nice side effect. Creating quality content and being active in whatever possible way, makes Hubbers successful to me. As MarleneB says....it fills you with joy. Just like it fills me with good energy and new inspiration.
The most successful I can't name. There are so many out there:-)