by Tony Scwartz

It's one of the hardest things in the world to do, probably because it runs so counter to our powerful and primal need to feel safe, loved, and successful.

For most of my life, I prided myself on relentless perseverance in the face of obstacles, and a refusal to give up on any goal or client I was pursuing. Letting go felt like failure or rejection, and both were nearly unbearable to me.

I have no doubt that pushing so hard has influenced whatever success I've had. Increasingly, though, I've come to believe it exacts a toll that no longer makes sense or feels acceptable.

At the most practical level, pushing continuously against resistance burns down our available reservoir of energy, and makes us less capable of doing anything well. Beyond that, pushing too hard can end up getting you what you think you want, only to discover, too late, that there was a good reason it didn't come together in the first place. Resistance is an early warning signal.

Several weeks ago, a senior HR executive at a large company invited me to dinner after hearing me speak. He spent much of the dinner explaining why his firm wasn't inclined to create a more flexible work environment for its employees, and how he hoped he could find a way to introduce our work under the radar, and then slowly build interest in it.

"You know what," I heard myself saying, "I don't think our work is right for you at this point." He looked slightly stunned. In all honesty, so was I.

I couldn't quite believe I'd let go of a potential client who had explicitly expressed interest in our work. But by the end of the evening, I felt lighter, as if I'd done the right thing for both of us.

The next week a CEO who had long claimed high interest in our work, but had never moved forward, wrote asking if we could introduce our work to his team in one-third the time we had suggested.

Sure, it was possible. But we'd have been eviscerating the heart of what we do, which is grounded in giving leaders sufficient time to truly reflect on the way they're working, and to recharge. I wrote back and declined.

Don't get me wrong here. I'm not suggesting the way to build a business is to regularly turn down opportunities. But not every one makes sense. I believe deeply in the value of the work we do, but I also know it only sings in a supportive and nurturing environment.

Letting go of half-hearted clients frees up time and energy to invest in clients who passionately share our commitment to reenergizing the workplace in a world of infinite demand.

The larger point for me is that foregoing opportunities may be less a sign of failure than of careful prioritizing and intelligent sacrifice.

Likewise, learning to let go when it's clear you're not getting what you're after — to accept a "no" without trying to turn it into a "yes" — not only saves energy, but also dignity, which is no small contributor to our well-being.

What makes it hardest to let go of anything we want is the assumption that we'll feel an enduring sense of loss. In reality, we're terrible prognosticators of the future. "Negative events do affect us," as psychologist Daniel Gilbert put it in his book, Stumbling on Happiness, "but they generally don't affect us as much or for as long as we expect them to." Nothing is as important as it seems in the heat of the moment.

With all that in mind, I've come up with four questions I now ask myself each time I begin to wonder if it's time to ease back on something or someone I've been pursuing.

Here they are:

1. Do I have a feeling in my gut that this dog just won't hunt? 
2. How important will this seem to me in six months? 
3. How important will this seem to me in two years? 
4. Is there a more enjoyable and productive way I could be investing my time and energy right now?

If the answer to 1 and 4 are "yes," or the answers to 2 and 3 are "not much," it's time to let go.