This is a very useful concept that doesn't just apply to learning martial arts but to learning any skill.
There are four stages of learning.
Stage 1 - Unconscious incompetence
This is where you are screwing everything up but you don't yet realize you are screwing it up. For example, Dropping your hands when you punch, trying to bench press your way out of mount.
Often students will stay in this phase much longer than is necessary because of either
A - They are not being given feedback (either verbal feedback - 'Keep your hands up' or Physical Feedback - Getting your teeth knocked out because you didn't have your hands up).
B - They are having some success even though they are using terrible technique. For example, Your training partner taps to a submission even though it was incorrectly applied.
Stage 2 - Conscious Incompetence
This is where you start to learn and develop. Its at this stage that you start to be critical of your own technique and begin to figure out exactly what you are doing wrong and what you need to do to improve.
Examples include - 'Why am I getting kicked in the leg so much? Why can I not escape mount position? Maybe I'll pay more attention the next time coach shows us that technique'
Stage 3 - Conscious Competence
At this stage, you know exactly how to perform the techniques properly and when to do them. You can figure out what you need to do and what to work on. However, you realize that there is also the possibility to lapse back into bad habits if you lose concentration.
Stage 4 - Unconscious Competence
This is the final stage of mastering any skill and this is a common trait with all great champions. They perform the skill perfectly without having to think about it.
Don’t practice until you get it right. Practice until you can’t get it wrong.