I love reading “The Corner Office” column by Adam Bryant in the New York Times on Fridays and Sundays. Adam talks with CEOs and other leaders about management and often asks about the lessons they learned on the road to success.

It’s refreshing how honest many of these leaders are. Yesterday, the column was about Penny Herscher, who is CEO of FirstRain, a business analytics firm. She admitted that she has a strong personality and started out too autocratic, sure she was right all the time. People told her they didn’t want to work for her, or they just left the company.

She mentions a mentor who made a big difference in her life. “He was one of the only people who would hold up a mirror to me and say, ‘O.K., that wasn’t good.’ I needed somebody who would tell me the truth. Many leaders with strong personalities never hear the truth because their people are afraid to tell them. The people who will tell you the truth are the most valuable people in your life.”

Bingo! In my career as a turnaround authority, I’ve seen so many companies in dire situations, on the brink of failure or bankruptcy. Sometimes the root of problems isn’t that hard to determine. Many of the employees knew it. Many in senior management knew it. But no one wanted to tell the CEO the truth.

Usually it’s because they fear losing their jobs, they might be punished, or ostracized, or they have tried several times in the past and their suggestions were ignored.

Every CEO or business leader has to have someone who will deliver the truth, no matter how unpleasant. You can’t fix what you don’t acknowledge.

I read an article online about a company that says it only works with “enlightened leaders.” The title of the article is “Destructive Leadership Practices: Is Your CEO in Denial?”

The author, Jeannie Walters, writes about a time she worked with a growing technology company that had a successful product and received a lot of press. But the high rate of employee turnover was hurting it and great talent didn’t stay.

Turns out, the CEO was “inflexible and demanding. They were too fearful to tell the truth about feeling overworked and under appreciated. Every new employee learned the secret code of ‘don’t ever offend the CEO,’ which also meant never critiquing his original work. This included the design of the logo (it was awful) and the user experience of the very product they were selling.”

She presented her findings about the company to the CEO, which were confirmed by the marketing director during the meeting. He didn’t want to hear it and declared all the information was wrong. Fast-forward a few months: the marketing director is gone and the company eventually shut down.

You’re most likely not going to like hearing about which areas are not working in your company, whether it’s that your management team isn’t functioning, your relationships with your vendors are not good or your business is not as well off financially as you thought it was.

Every CEO needs at least one truth teller in his or her life. You don’t have to like it, but you do have to make yourself open to hearing it, believing it and acting on it. It helps to remember that while you may go through short-term pain, it’s all for long-term gain. Don’t be a CEO in denial.