I rushed to get my filet mignon order in three minutes before the kitchen closed. To me, a trip to Chicago is incomplete without steak enjoyed in dim light, over dark wood, in a nearly ancient (at least by US standards) restaurant.

I also feel I deserve it. First, I’m only here for one night. Tomorrow, I run a four-hour Outthinker workshop for 120 entrepreneurs then jump on a plane to Omaha (more great steak!) to kick off a strategy for a maid-service franchise company.

Secondly … due to bad weather, my two-hour afternoon flight turned into seven hours banging away at my laptop in an airport, as a result of which my inbox shrunk from 200 messages to two. And now I feel too energized to sleep.

And that is the real insight I want to share. When your inbox is filled with unread, unconsidered messages, you never really know if you are missing something.

And I’m not speaking just of electronic messages. This is true for strategy as well. When your organization has not looked through its inbox of strategic options and decided whether to trash or implement each one, your people will be pushing forward half-heartedly, always wondering, “Have we considered everything, is this really the best path, is there something else we are missing?”

And that will sap them of their energy.

Sun Tzu advises to march your army deep into enemy territory so there is no easy, alternative means of escape. They need to fight to the death.

Recently published research by some Wharton professors shows that when people believe there may be a “plan b,” they try less hard to make “plan a” work. They asked students to solve a math problem in exchange for free snacks. They asked half of the students to think about, before they started the exercise, where else on campus they might get free snacks. Those students, who had contemplated the alternative to getting free snacks from solving the math problem, performed significantly worse than those who had not thought about the alternative.

It’s like my son who crawled into our bed last night. He could not sleep because one fearful thought kept penetrating his slumber – “Is there something under my bed?” Now, to my wife’s dismay, I so love snuggling with my kids that I would never test this hypothesis, but I’m willing to bet that had my son looked under his bed and seen there was nothing there, he would have slept in his own room in comfort, knowing there was no unknown, unconsidered “thing” to disrupt him.

Consider all the possibilities, kill off all of the other options, empty your inbox, look under the bed … Then you can commit fully to the path in front of you. That will give you commitment you need to succeed.