There's no justification to call him a bad worker or a dangerous one. His in-ring skills are different from those of most of the wrestling industry's because his size and athleticism are so unusual. He's a true power wrestler (much like Goldberg), but he seems able to work a match for more than 8 minutes. So, his skill set is different from Punk's or Bryan's (who have very technical movesets) or from Cena's (who has a moveset that promotes his own unique mix of size and quickness). As a true power wrestler, he can just do power move after power move and destroy guys. He seems to work pretty stiff but that doesn't make him dangerous. As for the "roided-up freak" charge, I'd like to see evidence that he uses steroids if you're going to make such a charge. He looks huge (obviously), but not unnaturally so. Also, to my recollection, he's never been suspended from WWE for violating the wellness code, so...
As to why he's never held a title, it's because it's never been advantageous to get him a belt. I figured he'd win the IC or US Title by now, but he blew right past the midcard into the main event scene last year. He's due for a title reign (it wouldn't surprise me if part of the reason for putting Cena into the WHC scene was to have him feud with Ryback and lose the belt to "the big guy"), and he'll probably have one before too long.
The best quality a pro wrestling fan can have if they're going to pick a favorite wrestler to favor above all others is patience that they will eventually see their guy get to the top. It worked out for us Punk fans with an ultra-long WWE Title reign. It'll happen for Ryback fans, too.
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