Among other things, the SEAL told Itzler that Navy SEALs have a 40% rule. Essentially, when we push ourselves, rather it be mentally or physically, our minds will tell us we have nothing left to give once we have given about 40% of what we actually have. This means that we have 60% left. The SEAL reminded Itzler to control his mind and to realize that the first few times his mind told him to quit and give up on a task, that he had much more left to give and to push through - DO. NOT. QUIT.
The 40% rule certainly applies to all of us professionally, if not personally. At some point, if it hasn't already occurred, your mind will tell you that you have nothing left to give to your family, friends, or job, or that you just can't put up with someone anymore, or that you've done everything you can for someone in your life and have nothing left to give. When this happens, remember the 40% rule. You still have much more to give.
For the video and transcript of Itzler's experience with the SEAL, click http://bigthink.com/videos/jesse-itzler-on-living-with-a-navy-seal