Are League of Legends Players/Entertainers Quitting?

I had stumbled onto YouTube.com today, only to find that there's a video about a professional esports player named, Dade, former SAMSUNG BLUE midlaner that almost won worlds, sadly lost and switched to the team M3, lastly Newbee before retiring, only to never be seen again, and I did some research and found out that it's very common for a professional player to boom up, then slowly die out. The exact same scenario happened to Looper, another professional gamer, whom appearantly was very popular, and then soon was left team less, only to go into retirement. So, what's with all of these players leaving the professional scene, and why are they doing it, more importantly, how? Could they have just gotten bored of the game, because most of them still play, like Dade, but off stream and just Korean soloq. This is off topic, but why is it that people are quitting this game all of a sudden, people are quitting, like ArKaDaTa, Pokimane(not that I watch her to say the least), NEACE, and NightBlue? Are they simply getting bored of the game, community, or have they found better games?