Why are people constantly playing champs they're never played before in ranked

Like a million times in the upper half of gold I've seen people on my team pick champs they have NEVER played before in ranked, or have simply NEVER PLAYED BEFORE PERIOD. Like, a LOT of times. One game I had an Ashe who, I looked deep in her op.gg page, had literally NEVER played the reworked Ashe before. AND she was not an adc main, but first picked adc. So yeah, she fed super hard... And then another game I had a Fiora jungle who, no surprise, did not have a single ranked game on Fiora, and also did not have a single game on Fiora as far as I went in her match history, AND did not main jungle, yet first picked Fiora jungle. Another one I remember is a game where I had a different Ashe who even said ingame that she had NEVER played reworked Ashe before. And there was one time I had a Rumble who first picked Rumble and did not have a single ranked game on Rumble, and didn't even main top. I found that he had ranked games on a great many champs, and really did not seem to main any... And there have been many, many other times this has happened for which I can't remember the specifics.

Why the fuck are so many people in ranked SO FREQUENTLY first picking champs THAT THEY HAVE NEVER PLAYED BEFORE for roles THAT THEY DO NOT EVEN MAIN????????