martacarl

I got this,...

I've never watched that much tennis on grass, except the last rounds of Wimbledon occasionally, mostly the big 3 matches. And when I was younger and watching TV with my father I've always been told (and always understood) that grass was the fastest surface and favoured agressive players, serve, volley, etc. Hard courts were also seen as "fast", mostly. Meanwhile, clay was a super slow surface and favored long rallies. So I have a question, how is it possible that some players have such different levels on hard and on grass ; because I've been told that the 2 surfaces were kinda similar ? Like how can Medvedev be an insane hard court player, but at the same time be pretty average / bad on grass ? I can see people being good on hard and grass, but bad on clay, because clay is a pretty special surface that can punish attackers to the benefit of more solid and defensive players + the different bounce, the slides, etc. But seeing people being good on hard and bad on grass is a mystery to me. It's probably because I have a wrong idea about how grass courts actually are, please unlighten me about that.