Why do I get +16-18 lp when I win but -21 when I lose?

The op.gg MMR isn't your real MMR, it's a guess. The real MMR value is hidden and isn't accessible via League's API.

This guess can be right, but it can also be horribly wrong, like in your case. The best way to estimate it is to look at who you tend to play with/against.

Regardless, I suggest that you simply ignore your LP losses/gains and play to improve, as you should be trying to do that whether you're plat or bronze. Your rank is just distracting you for now. Focus on improving, then you can start to turn your MMR around and climb to gold.

Also, you're not being matched with people worse than you, people in League get matched by their MMR, regardless of their rank. I'm guessing you went on a bad loss spree at some point, due to tilt and/or bad luck, which dropped your MMR. So now you're playing with Silver 4-5 players. They aren't necessarily worse or better than you, they're just of equal MMR to you.

If you want to prove the system wrong, keep winning and increase your MMR, and you'll start to play with higher-ranked players. If you can't do that, the system will be right, and your high LP losses will eventually force you down to Silver 4-5, where your gains and losses will go back to equal.

Op.gg is not accurate only riot knows youe mmr.

[{quoted}](name=Ah 9h 7cch,realm=NA,application-id=3ErqAdtq,discussion-id=LXO8Ktcl,comment-id=0000000000010000,timestamp=2018-01-31T09:47:25.722+0000)

Explain to me why op.gg tells me I have silver 2 mmr then. While you're at it, explain to me why I'm being matched with/against people worse than me.

That is a third party calculation based on recent games won an lost and does not accurately reflect your real MMR.

[{quoted}](name=Ah 9h 7cch,realm=NA,application-id=3ErqAdtq,discussion-id=LXO8Ktcl,comment-id=0000000000010000,timestamp=2018-01-31T09:47:25.722+0000)

Explain to me why op.gg tells me I have silver 2 mmr then. While you're at it, explain to me why I'm being matched with/against people worse than me.

because you are bad. op.gg is not accurate , it says on average whats your mmr , not your exact mmr. Play good , get more lp , easy.

[{quoted}](name=Ah 9h 7cch,realm=NA,application-id=3ErqAdtq,discussion-id=LXO8Ktcl,comment-id=0000000000010000,timestamp=2018-01-31T09:47:25.722+0000)

Explain to me why op.gg tells me I have silver 2 mmr then. While you're at it, explain to me why I'm being matched with/against people worse than me.

... really are we doing this again... becuase op.gg MAKE ITS UP that is one of thier "gatchas" to try to get you to thier site... they also dont use NA data... at the stats on na.op.gg are from KOREA not from NA (in case u have never hovered over that little ? mark icon in the top right. they make some some excuase that "there isnt thjouygh data on na to get info so here is korean data) and they make up your mmr based on thier own little calculation.

just becuase u see "na" in the url. u dont read what the site actually says.

seesh how do people not know this by now.

dont use op.gg

there is nothing that can tell u your mmr.

if u want site that give accurate info try "league of graphs" and champion.gg

op.gg is a joke that has no relevant data outside of plat + korea.. which i HIGHLY doubt affect you or anyone who isn't challenger on NA.. and therefore anyone actually reading this post