Dragonball Z plays perfectly to the little boy who wants to grow up and be strong. If you don't fit that category or watch it too late in life, you won't get it. If you did catch it during the golden viewing period, you'll probably look back fondly on it for years to come. That's my story, anyways. DBZ (along with some other stuff like World's Strongest Man) actually motivated me to become a competitive powerlifter.
There's nothing like it; the fights are so over the top epic with characters being punched through mountains, the world is fantastical yet simple enough for a young kid to understand, and no matter how crazy strong the heroes get they always have to train their asses off to get there, giving the illusion that maybe you too can someday be a superhuman if you try hard enough. And despite the many flaws when one is looking for a well written narrative, I do truly believe Dragonball had a very unique and creative world behind it.