I dare you to search "smurf" on the boards...See what comes up (AKA How to beat a dead horse)
I know you are lazy so here i did it for you https://boards.na.leagueoflegends.com/en/search?query=smurf&content_type=discussion
This is a page full of smurfs looking for other smurfs to duo with. Why? Because smurfing which is already borderline against ToS isn't bad enough, they want to duo smurf to make sure there isn't a smidgen of real competition left in any game.
In my last 10 ranked games in plat 4 i have had 3 diamond or higher smurfs. 2 on the enemy teams, one on my own. These games are predetermined, no matter how positive i try to be or how hard we try, 90% of the time the team with the smurf (or smurf duo) is going to win in plat (which is basically gold, trust me its where I've been for a long time).
One of the smurfs that beat my team was even streaming on twitch, and i went into his room to ask it he realized he was ruining the competitive nature of ranked, and i asked if he had to start a new account due to a ban or lost account, and he said "no, i just like crushing in lower elo sometimes."
I know smurfing is a complicated issue with no easy solution, I've been reading up on it for the last hour, but doing nothing is not acceptable. The game has enough issues as it is that we players put up with because we love to play, but i can't bring myself to queue up again knowing i have a 30% chance of getting a smurf in the game based on my match history.
Hit me with those thoughts