Among the reasons that companies hire executive coaches is to provide senior leaders with a sounding board.

While this is something I have long suspected, I was pleased to see it confirmed by the results of a small survey of veteran executive coaches conducted by Alexcel Group, a coaching network to which I belong. Two thirds of the coaches surveyed said their engagements involved being a trusted advisor able to provide much needed objectivity.

A reason for serving as a sounding board is rooted in trust. Not too long ago I did a seminar for CEOs of small businesses. In the course of my talk I mentioned that none of the attendees had any real friends inside the companies they owned and operated. That comment provoked a strong negative reaction.

I held my ground and challenged the group to consider that each of them had the power to hire, reward, and terminate any employee in their organization. Then one CEO looked to his colleagues and said something like, "He's right! We may not have as many friends as we think we do!" I don't think that I won over any converts but at least they allowed me to continue speaking.

Many CEOs with whom I speak talk about it being lonely at the top. They are not asking for pity—when you have access to the corporate jet, life is not all bad. But the wise executives I know realize that being in charge means you are always making decisions that have big consequences for others.

Most executives love the impact their decisions have, but at times, they know that decisions they make about opening or closing facilities, promoting this executive over another, or deciding which business to pursue or which to pass on, has real impact on people's lives. As Shakespeare wrote in Henry IV, Part 2, "Uneasy lies the head that wears the crown."

To paraphrase the Bard, I would say senior executives do not readily surrender their crowns but from time to time like to take them off. Enter the executive coach. His or her role is to encourage the executive to look less royal. That is, take a frank look at themselves and their roles in the company.

Good coaches I know do not pull punches with feedback they deliver. They seek to be honest brokers with ideas, opinions, and suggestions they gather from stakeholders. Coaches also listen and learn from what an executive says, and seek to share expertise in helpful ways, especially to challenge assumptions.

The obstacle for the senior leader is the desire for straight talk beyond the coach.

The man or woman at the top of the pyramid must work hard to enable people to speak truth to power. That is not easy. None of us likes push-back, especially when we are working hard to get things done right. But for those who report to a senior executive telling them the truth may be what's most important.

And so let me close with a story that General Omar Bradley recalled about his former boss, General George C. Marshall, who served as U.S. Army Chief of Staff during the Second World War. In 1939, as America began to mobilize for the eventuality of war, Marshall chastised his junior officers for their failure to disagree with him about his planning strategies. Marshall made it clear that he did not want yes men on his staff; he wanted officers who were not afraid to question his decisions.

That's a good lesson for every leader to keep in mind.