Before youtube disabled recommendation for people with watch history turned off, having watch history turned off made it so your recommendations were only based on channels you are subscribed to and possibly videos you’ve liked, commented on, …

There are some categories where I only ever search for the category, then watch a video, but never subscribe to any channel. Those videos were never recommended to me. Meanwhile on my girlfriends pc with watch history turned on, as soon as I watch a single video from a channel she’s not subscribed to similar videos appear all over the front page.

Every Rubik’s Cube, no matter how scrambled, can be solved in at most 20 rotations.