Let's imagine a graph. Two axes: Something good vs. time.
In math this is pretty clear to see, but I think the principle behind this truism is something that helps to apply to other fields as well. A lot of times among my classmates, we mentally jostle by comparing ourselves to the ace guy in the room who had 3 years of programming experience, worked an internship in high school, and was at Google last summer. And I think this seems to put a mental block in a lot of people and prevent them from trying new things and entering new fields. In a lot of places, and especially here at Stanford - people tend to emphasize how much they know and not how fast they're learning.
That's good news for all of us because we're young and in a place where we can learn really really fast. You don't have to do anything heroic. You know the difference in slopes doesn't have to be that great if you just every day think about learning a little bit more and getting a little bit better, lots of small steps, its amazing how quickly you can catch up and become a real expert in the field.
One practical thing you can do is ask yourself at the end of the day: have I learned one new thing today? It might be different from day to day and the particular field you happen to be learning in. But if you just think about your slope and don't worry about where you start out you'll end up some place nice.
As we continue to push upwards towards more difficult problems, we're developing a long-lasting habit that starts to permanently skew our line of comfort to be steeper and steeper.
[inspired by Professor Ousterhout: quora link]