I've frequently written about the beliefs, strategies and tactics that make good leaders into great leaders. However, great leadership also requires clearing your mind of beliefs and thought patterns that make you less effective.

According to Dan Prosser, author of the newly published Thirteeners: Why Only 13 Percent of Companies Successfully Execute Their Strategy, weak leaders (or "pretenders" as he calls them) tend to share these dysfunctional beliefs:

1. "It's my employees' fault we're failing."

The inner monologue: "The market is bad and business is off. I need to find out which employees aren't pulling their weight so I can weed them out. They seemed so promising when I hired them, but they just haven't worked out. If they're going to survive, it's going to be pretty much up to them."

What strong leaders think instead: "I'll need everyone's help to turn this around."

2. "Bad government is killing us."

The inner monologue: "My business is suffering because the market is down, the government is inept, or the banks are full of crooks. There's nothing I can do to change any of that other than complain about it, as frequently and as loud as possible."

What strong leaders think instead: "There's always a silver lining; I just have to find it."

3. "We need a new strategy immediately!"

The inner monologue: "Our plan is proving more difficult than I expected. We're encountering obstacles and not growing as quickly as I thought it. The problem must be in our strategy, so we need to go back to square one and create a brand new strategy, even though it means scrapping everything we've done so far and starting from scratch."

What strong leaders think instead: "I must decide how to overcome these obstacles."

4. "We're way too busy to lay groundwork."

The inner monologue: "It's chaotic enough around here with all the problems we have getting the work out the door and serving clients. I'm trying to get rid of the chaos so we can get some work done. I wish we could find time to work through basic issues and prevent future crises. But what's important right now is put out all these fires."

What strong leaders think instead: "I must address the root problem even if it means ignoring a crisis."

5. "Our product doesn't sell because it lacks features."

The inner monologue: "Everyone knows that 'if you build a better mousetrap the world will beat a path to your door.' Since nobody is beating a path to our door, the problem must be that our product isn't 'better' enough. Therefore, our priority should be improving the product rather than selling the product we've got."

What strong leaders think instead: "How can we describe our product so that customers value what's unique about it?"

6. "No matter what, I must appear successful."

The inner monologue: "If something goes wrong, then everyone will realize that I'm not as clever as they thought. Therefore, if I'm not 100% sure of the outcome, it's best to avoid the risk. If I can't avoid the risk, then my number one job is managing appearances so that I don't look like a failure, even if the project fails."

What strong leaders think instead: "I'd rather try something bold and fail publicly than timidly do nothing."

7. "It's OK for me to break promises."

The inner monologue: "Being held accountable for the growth and profitability of a company is scary and difficult. Therefore I'm justified in making promises I can't possibly keep and failing to keep the promises I make."

What strong leaders think instead: "Trust holds teams together so I only make promises that I can and will keep."

8. "It's my way or the highway."

The inner monologue: "I've been in business for years, I know what it takes to be successful. My employees need to do it the way I did it and if they don't it's because they're not listening. I simply don't have time to sit down and have discussions with people about what they think should be different what needs to change."

What strong leaders think instead: "To be successful, we'll need the skills and experience of everyone on the team."

9. "My employees are like my children."

The inner monologue: "I started this company so I'm the head of the family. My employees are my children and, like children, should do exactly what I tell them to do. If they don't, I'll just have to call them into my office and give them a verbal spanking."

What strong leaders think instead: "My employees are responsible adults who deserve to be treated with respect."