Vishen Lakhiani explains the 4% rule: pick projects just 4% harder than you think you can handle to trigger flow. He uses a concrete example like finishing an 8-hour task in 7h45m to create time pressure that forces new approaches and faster skill growth.
Chapters
Science shows there's a simple way to enter a flow state, and it's called the 4% rule.
If you want to grow in any field, you want to be able to enter flow states where you are so engrossed in your work that you are growing, you're getting better, and you are excited about the work you do. And there's a simple rule for this. Always ensure that the projects you're working on are roughly 4% harder than what you think you're capable of. The 4% harder rule puts you at just the right zone where the project is challenging enough, where you can develop flow and you can grow. A simple way to do this is a timer. For example, if you're a writer, if you know that a particular blog post or article might take you 8 hours, seek to do it in 7 hours and 45 minutes. It gives you the right amount of challenge that puts you in flow, but causes you to grow because you have to think of new processes, new ways to get your output done in a tighter time. As a result, you get better and better, faster.