Your words have power, and they're among your most important tools as a leader.

But what's just as important as the things you should say every day? The times you should keep your mouth shut.

Here are 10 examples. (Got others to suggest? Let me know.)

1. I'll do it myself.

Deadlines are looming. You've got 50 things going on. The last thing you have time for is to teach someone else how to do his or her job, and the temptation is to step in yourself and do what needs doing. However, a leader has to delegate. Otherwise, productivity problems will persist, and your team members won't have the chance to learn and contribute.

2. I'll deal with it later.

Does bad news ever get better with age? Only with luck--and you're not leading a team or building a business based on luck. Deal with it now.

3. I'll give you one more chance.

It's almost always easier to overlook flaws--whether they're in an employee, a customer, or someone providing a service to you--than it is to deal with difficult situations. But you're probably not doing any favors by being a pushover. Be as kind and generous as you can while putting your team's goal first, and make the hard choice.

4. Let's put it to a vote.

There will be times when your team disagrees among themselves. Sometimes they may all agree with each other--but disagree with you. The easy way out of these situations when a decision has to be made is to punt, by trying to let democracy solve the problem for you. That's not what a great leader does, however. When you're in charge, act like you're in charge.

5. I'm sorry to ask you to do this...

Never apologize for asking someone to do his or her job. (But do be polite. That costs you nothing.)

6. You're fired.

There's a smart old adage: Hire slowly, and fire quickly--and when somebody isn't working out it's your responsibility to rectify that situation. The trick here is that a great leader never actually uses the word "fired." Instead, you want to manage people's exits so that whenever possible, their transition out of your organization is graceful and leads to better opportunities for both you and them.

7. I don't care what you want.

Really? The leader who says this is either exhausted, inconsiderate, or foolish. Of course you should care about what your employees or team members want. That doesn't mean you should accommodate every desire, but they should know that at core, you care about what they care about.

8. We can't do this.

Former Secretary of State Colin Powell used to say, "Perpetual optimism is a force multiplier." The opposite of that is true, too--if your team gets the sense that you don't have confidence, you're probably soon-to-be done. Be realistic about challenges, but never let your fear win the day.

9. None of your business.

There are some things you probably need to keep confidential. Sometimes you need to control the timing of when news gets out. But by and large, transparency and honesty are the best policies.

10. Never.

There are exceptions to every one of these rules. So "never" is a very strong word, and "never, ever" is even more ill-advised.