I am not a fan of Youtube's recommendation system either. I think it favors too much "more of the stuff you recently viewed". Sometimes I watch 4-5 videos on a subject, then I move on but my feed keeps contaminated suggesting more about those things over and over again.

Youtube should really trying recommending stuff that's not "exactly the same as you saw, but from a different channel".

Also, for some weird reason (and partially contradicting what I said above) Youtube has been insisting in suggesting Jiu Jitsu videos to me for a very long time. Sometimes I watch MMA-related or Muay Thai-related stuff, but never Jiu Jitsu stuff. And it insists on always showing me Jiu Jitsu stuff.