Traders log thousands of hours and plateau early. The research on expertise has a consistent explanation: hours alone do not produce skill. Deliberate practice does, and it has conditions most screen time fails to meet.
A specific target, not "get better"
Practice needs one thing being trained. "Improve my trading" is not trainable. "Stop moving my stop after entry" is. A session with one target produces a readable result; a session with five produces a story.
Immediate, unambiguous feedback
The feedback has to arrive close enough to the decision that you can still remember why you made it. A monthly P&L review is too late — by then the reasons are reconstructed rather than recalled.
This is where replay has a structural advantage: the outcome of a decision arrives seconds after the decision, still attached to the reasoning.
Repetition at the edge of your ability
Setups you already execute well are not training. Neither are ones far beyond you. The useful zone is where you succeed roughly half the time and the failures are informative.
Discomfort you do not avoid
The parts that feel bad — sitting in drawdown, taking the signal after three losses, passing on a setup that does not qualify — are the parts that need the repetitions. Practice that feels good is usually practice of what you can already do.
None of this requires a simulator. It requires that whatever you use gives you uncertainty at the decision point, feedback right after it, and enough repetitions to make the pattern visible.
On the first condition, why bar-by-bar replay beats scrollback is the longer argument; on the third, compressed practice time.