I think .Net is too huge for one person to learn it all, and it's just getting bigger - like a galaxy. However, sometimes an optimistic developer may get the temporary delusion that they can learn it all, or at least the parts that matter. How could someone become so optimistic?
- Unexpected free time.
- Something came easier than expected.
- You're on a prestigious fast track project.
- A real good teacher explained something very well (and quickly).
- You're kidding yourself - you're just skimming, or only looking at buzzwords, not really digging into the tech.
Basically, if things are temporarily going well (i.e. you're absorbing new concepts really fast), it may be tempting to think that "ah ha, this learning thing has finally clicked, and it will always go fast from now on!" Oh, how I wish...