Good managers want to know when they've made a wrong decision. Bad managers, on the other hand, make excuses, blame others or deny they've made a mistake. If your manager belongs in the second group, you’ll have to take a careful approach to questioning her past decisions. Your goal should be to voice your concerns clearly, spurring your manager to rethink the decision without causing too much bad blood.
Get Your Facts Straight
Before you confront your manager, gather all the evidence you can to support your position. You might only get one shot at this, so you need to provide specific reasons why your manager made a questionable decision. For example, if you believe he chose the wrong strategy for getting a project done, identify specific reasons for your doubts and support each with meaningful examples.
Offer an Alternative
Your goal might only be to have management rethink its actions, but consider offering an alternative plan as well. For example, if you want your manager to reverse a strategic decision, having an alternative strategy ready will make changing her mind easier. As you did for your critique of the bad decision, collect all the evidence you can to support switching to your new plan.
Don’t question the decision publicly unless your manager specifically asks for feedback, such as during a group strategy meeting. A private meeting is a better arena for voicing concerns about bad decisions, if only because your manager won’t have to worry about saving face. Set up a private meeting at your manager's convenience. Let her know you want to talk about something specific to work. When you meet, explain your position as respectfully as possible and avoid being combative.
If you have a good manager, she will be grateful for your ideas and listen to them with an open mind. However, if your manager is bad or inexperienced, her reaction could range from passively ignoring your proposal to anger at being questioned. At that point, you’ll have to make a difficult decision, depending on the importance you put on getting her to change her mind. If the issue is relatively minor, you can content yourself with having tried to fix the mistake. If it's a big issue, however, be prepared to go to a higher authority.
If the issue is serious and you can't sway your manager to rethink his decision, you can keep pushing by going over your manager’s head. Just keep in mind that bypassing your manager is likely to make him look bad and create a permanent rift in your relationship. In some situations, however, employees are ethically bound to speak up, even when management makes that difficult. For example, if the outcome of the decision jeopardizes public safety or the welfare of the company, you have an obligation to bypass a bad manager to ensure the right people hear your message. Go to your manager's boss with your concerns and state them in a clear and professional manner, backing up your points with examples and data.