Sometimes, being overconfident can actually be useful. For example, when you behave like someone likes you—even when you’re not sure—you create a self-fulfilling dynamic where they may be more likely to reciprocate your behavior. When you are overconfident about how much influence you have over your attitude, you also choose to deliberately shape it.

Here are situations where being overconfident may help you:

• Saying hi to a person you haven’t met yet
• Reaching out to an old friend who you lost touch with
• Applying to a new job
• Starting a project, hobby, or business part-time
• Putting your fingerprints on a project at work
• Raising your hand to ask or answer a question

On the flip side, being overconfident can also be extremely damaging. Andy Grove’s famous book title, Only the Paranoid Survive, comes to mind. You want to be confident—not overconfident—when you’re taking an important risk or have put money or reputation on the line.

Here are situations where being overconfident may hurt you:

• Quitting your job without any plans or savings
• Delivering a good project on a tight deadline
• Assessing your performance relative to your competitors
• Forecasting your investment growth
• Preparing for the most important meeting of your week or month
• Finding happiness from achieving a goal