I've tasted Witcher 1. Wasn't able to get very far before giving up. Just too clunky & archaic for me, but I suppose I've given it enough time since then that I can try it again sometime.
I've given a decent effort for Witcher 2. Still strangely clunky & archaic, albeit with decent graphics & animations. Story still wasn't enough to get me past the clunk. It'll be a while before I have the will to try getting farther into that game.
I've started Witcher 3. Almost all of the issues I ran into with the past 2 games have been greatly smoothed out. For what little I've played of it so far it feels fairly enjoyable, unlike the last 2 where I had to struggle not to quit any sooner than I did. While I still hold very little interest in the story, bits of it are interesting enough along with smooth enough gameplay & graphics to make me actually want to continue playing.
I respect the Witcher series, but it's just one of those gaming experiences that *just* don't work with you personally. Maybe eventually I'll finish 1 & 2, but damn do those games make it hard for me to do. At least 3 seems like it'll continue to be decently enjoyable for me.