There are so many factors at play. One important one is environment...e.g. if your parents are chess masters and you've grown up watching them play, that's not being included as part of the 3,000 hours...and it should be, because the one with 10,000 hours might not have such an advantage.
As the plan progressed, the percentage of work dedicated to different training demands varied. By the time a trainee has pass into the final phase (Master of Sport International Class), he would only be performing the competition lifts for about 16% or 17% of overall training volume. The rest was taken up by a very large collection of assistance exercises, rotated as necessary.
After a while, the emphasis was on getting stronger. Their pattern of movement from tens of thousands of repetitions was sufficiently fixed that all that was left was maintaining the pattern and making them stronger.