Almost every adult improver hits the same wall at roughly the same spots: somewhere around 800 to 1000, again around 1200, again around 1500. You study, you play, your rating does not move for months, and it starts to feel like you have found your ceiling. You probably have not.
It is rarely a knowledge problem
Most plateaued players already know more chess than their results show. They know what a fork is. They know king safety matters. They know not to hang pieces. The problem almost never shows up as "I don't know this rule." It shows up as "I know this rule and did the opposite anyway, under pressure, for the fourth time this month."
White to play. The knight on d5 is simply hanging, no trick required, just noticing it's undefended. Everyone knows to check for this. Under pressure, in a real game, it still gets missed.
That is a retention problem, not a knowledge problem, and it needs a different fix. Reading another article about tactics will not touch it. What helps is seeing your own specific recurring mistakes, in your own games, often enough that avoiding them becomes automatic instead of effortful.
Progress you can actually see
Part of what makes a plateau feel so discouraging is that rating is a noisy, laggy signal. You can fix a real weakness and still lose your next three games to something unrelated, and the number will not move for weeks. That is demoralizing enough to make people quit.
Rookie deliberately tracks a different number: weaknesses cured. Every recurring mistake you drill until it stops showing up in your games is a concrete, immediate, controllable win, independent of whether your rating has caught up yet. It usually does catch up. It is just not the thing to stare at while you wait.
If you have felt stuck for a while, the fastest way to find out why is to actually look. Paste your Chess.com username and Rookie will grade your recent games for free, no account needed, and show you exactly where the points are leaking.