1. First hour. Outrageous optimism, ignorance, stupidity and naïveté are all critical at this stage.
2. 20 hours in. Beginner. Learnt the bare fundamentals. Growing confidence as you feel you're getting a grip on things. This wasn't as hard as you thought it would be.
3. 100 hours in. Intermediate level. Panic and terror sets in as you start getting into the deeper layers and nuances, and you realize you've barely crossed the starting line.
Most people give up here.
4. Advanced level. You truck on. Soon after, you'll push through your plateau and begin the rest-of-your-life quest for mastery.
Someone said something similar to this on a language learning forum (I am currently somewhere in stage three in learning the spanish language).
Thinking back over all the things I've learnt at a high level (copywriting, etc), I think it applies to pretty much everything.
The difference between stages two and three is that, at stage three, you know enough to realize how much you don't know.