Riot gives you bad team on purpose after 3 win streak!!! Or do they?
I've seen a lot of complaining and complot theories around this. If you go on a winning streak, Riot would give the enemy team good players and your team bad players to make your winrate 50% again.
I am a living example to proof that this is NOT true! I just finished my 10 placement matches (I was plat 3 with the MMR of plat 1 at the end of last season) and I won ALL my placement matches. And tbh... My team went from bad to awesome as my winning streak continued. During my first 3 matches, I had to carry my team to victory because everyone but me was (slightly) behind. During the last 7 matches, especially match 6-9, my team was just so good that I just had to go even against my laner to win.
What this means is that the relative skill of your team compared to their team is RANDOM and I just got extremely lucky and others just got extremely unlucky. That doesn't mean Riot is complotting against you or having a hidden agenda to boost my ELO. Winning streaks happen. And they usually continue until you have a bad team (or if you perform poorly yourself). This makes it pretty obvious that your team sucks "after" your winning streak, because if they didn't, it would probably still be your winning streak and the next game, or after 3 games your team would suck.
Note: My playstyle is very much based on the lategame. I try to get slightly ahead or even during laning phase, farming as well as I can and trying to help out other lanes during midgame. If your lane opponent is gone, either push down their turret or gank yourself (usually it's not a great moment to gank yourself so jsut push down that turret). A teammate might die, but your team also gets 100g per player to compensate. In the meanwhile, your lane opponent lost quite some farm.