Curiosity becomes awe when the answer creates more questions than it removes.

A good answer usually opens doors rather than closing them. You find out how one thing works and discover three assumptions underneath it that you had never examined. The moment where an explanation leaves you with more to ask than you started with is where plain curiosity turns into something larger, because you have just seen how much territory there is.

When you learn something, write down the new questions it produced rather than filing the answer as complete. Follow one of them. The chain that starts this way tends to go much further than any single topic you might have set out to master.