Not entirely sure how legit this post is considering it's in M&G, but I'll give it the benefit of the doubt.
You're at where you're supposed to be if you have a 50% win rate. If you want to climb higher then you need to have a greater than 50% win rate (even if it's only 51%, you'll climb a little higher until you reach 50% again).
Basically the elo system traditionally compares two players' elo ratings and calculates who is more likely to win. If the player who is less likely to win (the one with a lower rating) beats the higher rated player, they will gain a lot of elo, but if they lose, they only lose a little (the amount gained/lost depends on the gap between the players' ratings). On the flip side for the higher rated player, they're expected to win, so if they actually lose, they lose a lot of elo (usually equal to the elo gained by the person who beat them), and gain only a little if they win (also equal to the elo lost of the person they beat).
This system is usually used in Chess and other single player games (I think StarCraft uses this system too), but many multiplayer games have altered it to the best of their abilities to work for multiplayer games as well.
LP isn't actually calculated on this system, but MMR (an invisible rating that players can't see, but you can get an estimate from sites like op.gg) is (probably...). LP is calculated based on the average MMR of the League you're in compared to your own MMR, if your MMR is below average, then you gain very little LP and lose a lot, and the opposite is true when your MMR is above average.