That is a great quote. I think, this is why it's so valuable to monitor your progress. A friend of mine tracks her hours she invests in learning for university because she always feels like she is not doing enough but the numbers state otherwise. Another example is recording your training sessions when you lift or do any other sport that is measurable. When I was lifting, I would always record my performance of all my sets everytime I went to the gym. Because progress is almost always slow and often times only really visable in hindsight, it was a great tool for me to stay motivated. I saw myself in the mirror every day, so I couldn't see the growth of my stregth and muscles but my lifting diary told me that I got stronger by 10kg in timeframe XYZ. It was awesome to see that and always kept me coming back to the irons. And the irons always tell you the truth but that is another story I guess, you could transfer this to almost anything you do. If you want improve your shyness for example, say hello to a stranger 3 times per week. Then daily. Then have a smalltalk daily with a stranger, and so on and so forth. It will have an effect on you sooner or later. From my own perspective, just experiencing the self-efficacy on its own is a good feeling. And you can always build from your newly conquered territories. Have a nice weekend!