If youve spent a long time, like a whole last season and most of this one, at a lower MMR the LP gains can be very slow to increase. The more games you play inside the same 100-200 MMR range, the harder it is to shed the stink of "YOU BELONG HERE" Rito attaches to you.
It doesnt matter if you go on a 10 win streak, then go on a win 3, lose 1 pattern for a bit. LP increases will only go up about 2-4 points once the algorithm has decided where you belong. So if you were getting 15, then hit that hard win streak, you will have to maintain it for a while to increase gains; and I doubt you will see 20 LP gains if youve played over 100 matches this season on an account.
Part of the reason for this is it keeps people playing, and you have to have players "trying" or "hoping" to have a player-base. This is part of why I believe they DO throw in unfair mach making, so people have to play more to make up the losses. Promos are a great time to squeeze some more hours out of players cause their so SO close.
Sorry, good luck.
