Elo boosting and Riot possibly having an agreement with boosters/account sellers
First important thing regarding this matter you need to remember while reading this: Riot has said that they ban boosted/sold/shared accounts in waves to prevent elo boosters/account sellers knowing their method of detecting such accounts. Ban waves can happen at any time all of sudden. So everything seems to be fine at the first glance - safety steps taken by Riot to increase effectivness.
Now moving to the matter and why do I think there are two possible cases: either Riot has aa agreement with boosters/account sellers or their detection system has been long ago exploited and knowing Riot they can't agree to the mistake they made.
The most important matter right now which actually is most probably not known by most of the people. Price of elo boosting and things you get when you buy an account. Elo boosting costs literally nothing. Casuals, kids, bad players who want to be higher do not have to pay a fortune to get that gold border at the end of the season. Even plat border is nothing much. Do you know how much elo boosters want for a division in gold and below? 3$. Yes. If you are gold 5 you need to pay 15$ to get to plat. This amount can be payed from pocket money that kids get to buy sweets or toys. Literally they just don't eat sweets for 2 days at best and get to plat in that time. Prize from plat to diamond. Whooping 25$. Yes you heard me. ONLY 25$.
There are different boosters. Those who boost normally. those who boost excusively for placement games. There are also honor level boosters. And you know what else. There are actualy duo boosting methods. Yes they offer you they just jump on a smurf and carry you to desired division. They have 99% of success rate and if they fail to do that in certain amount of time they boost you one division more than you asked. They are 100% sure to succesfully duo boost people. And the amount of offers you see on sites like ebay and any other site that works like ebay (usually countries have their own ebay like sites very often) are just huge. You literally have hundred of pages with viable offers.
What is even worse. YOU CAN BUY LVL 32 ACCOUNT WITH 25K BE AND SOME CHAMPIONS AND SKINS FOR 5$. That's not all. They offer like 500 accounts ready to sell at once. They even say that if they wont have account ready to sell (they have system that sends you login and password through e-mail right after you pay) you need to wait at best 12 to 24 hours to get your account. THAT'S NOT ALL. THESE ACCOUNTS THAT COST 5$ ARE BY DEFAULT BOOSTED TO GOLD 1. AND THIS BOOST USUALLY MEANS YOU HAVE HIGH MMR SO YOU WILL BE MATCHED AT THE BEGINNING WITH PLAT 3-5.
FOR 5$ THAT IS AS MUCH AS SOME SWEETS THAT CHILDREN BUY EVERYDAY YOU CAN GET GOLD 1 ACCOUNT. BETTER. FOR 10$ THEY OFFER PLAT 3 TO PLAT 1 ACCOUNTS WITH EVEN MORE SKINS, CHAMPS AND BE.
30$-50$ for diamond 1 account.
This is ridiculous.
But I've been talking about prices and stuff, but what about my statement that says Riot may work with boosters? Here goes.
Every account seller GUARANTEES that account has 60 days of warranty. Why are they so specific? Ban waves for bought accounts and elo boosted accounts are done irregulary and suddenly. And here goes the thing. They know that, because Riot probably has agree with them to give the kids that buy these accounts time to enjoy their gold 1 or plat 1 rank, because if they spent just 5$ for their dream account in gold they will most likely buy skins on it which means easy and 100% sure money for Riot. Those ban waves and arguments for not banning these people right away is just a bad excuse to keep their agreement.
But let's actually think about the other case and leave the terrible idea that really appears more and more to be true on the side. What can be other reason? Like I said Riot has no control anymore over people elo boosting/selling accounts. Do you know what I saw in offers of elo boosters and account sellers? They say that during elo boosting or account leveling action, they kill all the possible league of legends process in their operating system. This is something they come up with to make it harder to detect for the system that account is elo boosted/sold. Which says that Riot pitiful excuse that ban waves are to prevent boosters knowing their detection technique is false in every aspect. This system has been already broken by elo boosters or riot told them themselves how to find a security bridge to avoid the system.
The lack of control over boosters though doesn't exclude the case that Riot is still working with elo boosters. They just dont work with every each elo booster because that would be close to impossible, so elo boosters who werent in agreement needed to find another way to make their clients accounts safe. Unfortunately everything has got out of control long ago. The changes in game balance that basically made many roles and champions into "pick me and spam this button for free win I stat check them anyway" is probably a pitiful attempt to make players not use elo boost that much and get freelo and boost themselves with game "mechanics" itself.
Anyway. Gold players aren't actually bad. They are pretty decent and can really carry games and do amazing stuff. The thing is that most of players in gold and even plat currently are "gold" and "plat" players who bought accounts or got boosted for actual cents. So if you see a gold/plat player keep walking into enemy jungle trying to steal camp for the 7th time while he seen whole enemy team going there and he makes rookie mistakes, you can be sure this account was boosted or bought. I remember 3-4 years ago you could meet such players but it was very very rare even in silver. Yes in silver there were are lot of decent players and getting completely bad players that you would usually see in bronze 5 was not a thing.
Not it is a thing in most divisions because elo boost and account buying is easily accessable, cheap and apperantly not punished at all or rarely punished.
This is sad, but Riot hasn't taken any steps. They just keep lying about their great undetected system when reality is completely different. Riot has shown already many times how greedy they are for easy money by changing the game to milk it as much as possible. You shouldn't be surprized if Riot didnt give a damn anymore about elo boosting/account sharing or simply worked with elo boosting services.