It's natural for focus and motivation to wane, for there to be times when you wake up, look at work and just feel . . . meh. But if you listen to the gurus, that experience can prompt ridiculous amounts of guilt. You'd be successful, the logic goes, but apparently you just don't want it badly enough. You'd be at the top, except you don't have as much passion as the other people.
What really makes a difference isn't the passion. You probably do have that. What really separates the people who make it from those who don't is the ability to handle boredom.
Think about it. We might have to spend weeks or months on specific projects, and sometimes it can take years to gather the information or skills we need to move to the next step. Now, science suggests that, on one level, one of the best ways to learn is to stick to one topic for a few months. But the brain also loves novelty and is distracted by it. So, you have to find a way to either make what you're doing seem super interesting again, which can be challenging even for the best of us, or find a way to keep showing up despite the feelings of meh.