The 10,000 hour rule.

The 10,000 hour rule. That is to gain expertise in any subject one needs 10,00 hours.
{This rule I saw on some blog.}

When I think about it I can see this is right. You have the normal four year program in a Lithuanian yeshiva. That means 10 hours per day at minimum of learning Torah. 10* 365*4 minus Friday and Shabat.

But I wanted to add the idea of critical mass. That is the hours can't be spread apart too far. That is it is not the same thing doing 10 hours per day four years in yeshiva as doing a few hours per day over a longer period of time. [Critical mass is the idea that not just you need a certain amount of mass but that the mass needs to be close together.]