That you should just make a decision and "eat perfectly clean" using nothing more than iron like self-discipline.
The someone else commented on the fact that eating better is more about building momentum than it is about attitude. How you need to get the ball rolling over a few bumps before you tackle the mountain.
Based on recent experience I believe it's the same for marketing.
It's about momentum and the tricky part for many folk is making sure they keep rolling forward. The easiest example is breaking the inertia with your first sale, then getting a consistent sale per week and then a sale everyday... and so on.
Same for your first web visitor or subscriber.
Then you have to maintain that momentum and not getting distracted. Because a change in direction is like trying to turn a rolling boulder around... you're simply making life hard for yourself.
Anyway... momentum is important. Probably why a few marketers choose to use it in their business names (? Lee McIntyre).