I realize that many athletes are training on their own during the current COVID 19 crisis. Most are training without a coach.
I know this might be a difficult issue to deal with, but it can have long-term effects on a lifter’s career. A bad habit developed early in a lifter’s career can be much more difficult to break than if the lifter had learned proper technique in the first place.
a neuromotor pattern
An incorrect or bad habit (“bad” meaning poor biomechanics) actually becomes ingrained in the brain. I’m not sure of the mechanism but I’m pretty confident that it involves some remodeling of the motor nerves and motor cortex. Once this pattern becomes established it will take over when the body reaches the point of initiation.
A common example that is easily observed and felt is footwork during the snatch and clean. Most people have not been coached to move their feet at the proper time and do so prematurely. This inhibits the full extension of the hips and knees and thus affects the speed of the bar in the pull. To break this habit, an athlete needs to fully plantar flex the ankles. But when trying to break the habit, most athletes will move the feet before achieving full plantar flexion.
It will take many more attempts to break this habit than it would have taken to learn it properly in the first place.
Incorrect motor patterns can also transfer over from other sport activities so one consideration for the beginner is to try to identify and eliminate them before they can interfere with motor learning of the snatch and clean & jerk. A daunting task but a doable one with conscientious effort.
It is entirely possible that an incorrect motor pattern cannot be eradicated for many athletes. Most that fail will do so because of a lack of perseverance.