I have a friend who talks about the flywheel model of learning. If, every day, you spend even 15 minutes towards your goal of what have you (aka, add even a little momentum to your flywheel), at the end of a year, you will have a lot of knowledge.
What she's done is pretty difficult -- executing a new concept daily -- and it's amazing she managed to keep it up when most others would drop out/fail.
I personally think "a lot of knowledge" comes through those lost hours spent fixing obscure, annoying problems and bugs and inconsistencies that force someone to really think through how that system works.
As Aristotle said: "We are what we repeatedly do. Excellence, then, is not an act, but a habit."