8 Enduring Lessons I Learned From My Clients in 2014 The smartest executives dreamed big, failed well and knew themselves.

Every year around this time, I like to spend a few weeks reflecting on the year and planning the next one. In 2014, I worked with executives in oil and gas, hospitality, accounting, utilities, engineering, construction, retail, steel, education, manufacturing, IT and banking. I've helped my clients become better leaders who built other leaders, develop and supercharge their teams, and hone their strategy and culture. And, as they do every year, in 2014 my clients have taught me some indespensible business lessons that we'd all be wise to heed in 2015.

1. Get ready to eat or be eaten.

In 2014, balance sheets were strong and companies saw M&As as a way to increase market share, broaden geographic reach, reduce corporate tax rates and add new customers, capabilities and technology. According to the Financial Times, "global deal making in the first nine months of 2014…eclipsed the level…in each of the past five years." I've had several clients make acquisitions—or be acquired. So whether you're in the market to buy, or you're in danger of being bought, you have to be ready. M&As are hard, and failure is common—usually because executives underestimate the impact of people and culture.

2. Dream big and execute ruthlessly.

I recently asked a client what his "non-negotiables" were. His company was at the top of its game, so his response was powerful: "My belief that things can always be better." In business, complacency is death. So for you, your team and your organization, even if you had a good year in 2014, what would it take in 2015 to have an exceptional year?

It's not enough to dream big. You have to set milestones and monitor progress. Never settle for "don't worry, we've got it under control." Lincoln did that with his generals in the early days of the Civil War, and it didn't go well.

3. Leadership is indeed largely learnable.

When I was in Dubai with a group of executives, I asked them an innocent question led to a vociferous argument: "Is leadership learnable?" There are a range of beliefs about this question. But unequivocally, this year more than any year before it, I can tell you with absolute certainty that leadership transformation is possible. Not only have recent studies supported this notion, I've personally witnessed profound leadership transformations with my clients. Mind you, this isn't easy—it takes self-awareness, a great coach, and ruthless accountability, but leadership is absolutely learnable—and it's never too late.

Related: 5 Ways to Train Yourself to Be a Great Leader

4. Teams that tell each other the truth always win.

Of late, I've seen team development produce dramatic returns. One executive team I worked with in 2013 increased their revenue by 20 percent in 2014. The president attributes the trust and honesty they built as a foundational factor. Another team was able to put issues on the table without attacking or criticizing each other. Their resulting process improvements improved on-time shipping, and they saw a 5 percent increase in net income in just a few months. In today's fast-paced business environment, taking time to build your team might feel frivolous, but the smartest executives understand that this is a key business investment.

5. Failure is not your enemy.

In many cultures, we're raised to avoid failure. But the ability to fail is one key factor that separates mediocre leaders from exceptional ones. Barbara Corcoran of ABC's Shark Tank fame (and the cover of Bankable Leadership!) says that failing well is "what separates the men from the boys and the women from the girls." In your role as an executive, if you're not failing, or allowing your team to fail, you're not innovating, and you're not taking enough risks. I'm not instructing you to tolerate sub-par performance; there's a difference between an informed risk that doesn't pan out and a stupid decision. How well are you failing?

6. Keep tabs on your top performers.

I am always amazed at how surprised some executives are when star performers leave. Smart executives understand that since their superstars are being actively recruited, they must keep tabs on how they're doing. You can't be so removed from their day-to-day reality that it's a surprise when you learn that they weren't happy. Also, their resignation letter is not a signal to negotiate. At that point, you've already lost them. For your best employees, you have to stay involved in their world. Conduct, or ask their manager to conduct, regular "stay interviews" that head off any retention issues as they arise.

Related: The Magic Equation for Retaining Employees

7. Manage individuals, not stereotypes.

This summer, I brought Bankable Leadership to a group of African business leaders. Their challenges were nearly identical to leaders from North and South America, Europe or the Middle East. Across jobs, industries, generations and cultures, humans are more similar than different but many leaders don't get it. I recently heard someone (not a client) say, "I'm going to stop sending my boomers to training. They just can't learn."

The research on generations reveals few immutable differences. It is intellectually lazy, and often illegal, to manage based on the group to which employees belong. My smartest clients consider results first and approach second. They understand that each person is unique. They manage individuals and not stereotypes. This seems so simple, but it's a difficult thing to do on a regular basis.

8. Self-awareness is the meta-leadership skill of the 21st century.

As you ascend the corporate ladder, you'll notice a bit of a Catch 22. Your actions become magnified, but fewer people tell you the truth.

Arguably, we live in a world where we have more information about ourselves than ever before (Klout scores, Myers Briggs profiles, 360 reports, etc.), but most leaders I encounter are not self-aware. On a most basic level, this means understanding what you like to do, what you're good at, where your passions lie. Self-awareness is also about acutely understanding the effect of your behavior on others and how you're perceived. The pinnacle of self-awareness means creating an organizational culture where people tell each other the truth. This year, I've seen a few executives do this well and the business results they see are extraordinary.

Related: Why Sucking Up Is Bad for Business (and How to Stop It)