What do you think is the top reason employees decide to quit? Did you guess more money? Not even close. A better title? Saner working hours? Nope and nope. Trying to get away from a bad boss? You might think so, but no.

Here's the No. 1 reason employees look for new jobs: They're bored with their old ones. That's the finding in a new Korn-Ferry survey of about 2,000 professionals. When asked what would drive them into the job market in 2017, an impressive 73 percent chose the answer: "I need a more challenging position." Needless to say, that response far outstripped any of the other choices. "My efforts are not recognized" and "I don't like my company" tied for second, with 9 percent of respondents saying each of those would be their likeliest reason for leaving. Only 5 percent said they would quit in search of higher compensation, and only 4 percent said they would leave to get away from a bad boss.

This is excellent news for everyone interested in keeping their best employees around. You may not be able to offer any more pay, or even a better title. But there is absolutely no reason--none!--why any of your employees should ever be bored with their jobs. If you aren't already doing the following, now is the time to start:

1. Learn to delegate.

Delegating, which means trusting other people to do things that you consider critically important instead of doing them yourself, is a huge challenge for many, many bosses--including me. But there are two truths to remember: The first is that if you don't delegate as much as you can, you won't get the full benefit of your employees' skills and intelligence, and your company won't get the full benefit of your leadership and other unique skills. The second truth is that no matter how much you train them, your employees won't always do things exactly the way you would have. They may not do them as well as you would have. Or they may do them differently or better. Whichever happens, it has to be OK.

2. Teach everyone their boss's job.

When employees leave--and inevitably they will--you're better off promoting from within than hunting for someone from outside. That means putting some effort into succession planning and making sure that every employee in your company knows how to do his or her boss's job. It can be unsettling for a manager to teach direct reports everything they need to take over. But it will make your company stronger and it will keep your best people around longer.

3. Switch things up.

Even if there's little room for promotion in your company, there's always room for sideways motion. One of the best ways to challenge bored employees is to invite them to learn to do work outside their day-to-day routine. If the sales manager learns how to take customer service calls, or the website person learns how to pick package designs, you'll be expanding their knowledge base, which will keep their brains fully engaged in their jobs. And you'll wind up with smarter, more well-rounded employees.

4. Take advantage of employees' own initiative.

The Korn-Ferry survey also showed just how badly all employees want to expand and improve their own skills. A surprising 82 percent of respondents said they planned to sign up independently for career advancement or professional development programs. More than half said they planned to enroll in classes, and two-thirds said they would participate in professional development programs sponsored by their employers.

Those numbers should tell you that your employees have a deep thirst for learning. Satisfy that thirst by both offering educational opportunities and training in-house and by paying for outside courses whenever it's feasible. And once your employees gain new knowledge, make sure you find ways to let them put it to good use.

That will keep your smartest employees around for years to come.