Board Thread:General Discussion/@comment-28702329-20181215114648/@comment-33951421-20190429174645

Diavolo is an extremely cautious character. The moment he sees himself injured in any way, he'll activate time skip. It's just what he does.

DIO is a massive threat, but Jotaro isn't. Not only is Jotaro's time stop 5 seconds max, which is half of Diavolo's time skip length (giving Diavolo plenty of time to time skip before Jotaro activated time stop) he lacks DIO's regeneration abilities so one hit from KC will donut Jotaro.