Towards the latter stage of his career he would take off 8-9 months where he concentrated on his band / music . I think during one of these periods he was touring in LA and Arnold invited him to the set of End of Days seeing his calling in Hollywood he quit competing to pursue his acting / singing career .
Also he had a lot of injuries which I believe was also a big factor - pec tear in 93 , compressed disc in 2000 ( I don't think he ever squatted again in his competition career ) , hernia in 2002 , tricep tear in 2003 and a torn meniscus for the last few years he competed which had surgery after he retired .
He's been talking comeback for the last five years at least but I don't seriously think he believes it . That said with the right motivation I don't doubt he could get himself in contest shape again he's probably one of the most gifted pro's ever and supremely talented . Hell the guy even held his own over 60 m sprint with an Olympic sprinter and European record holder over that distance . Remember this
The Kevin Levrone Race! - Bodybuilding.com