It's often said that every leader needs to think strategically. But what does thinking strategically mean exactly?

Nick Tasler, the CEO of consulting firm Decision Pulse, says that strategic thinking is about managing what to do and what not to do. "At the highest level, this usually means deciding to sell off one company in order to buy another one. More often it simply means deciding to move some initiatives to the back burner in order to concentrate the bulk of your resources in a single key area," Tasler writes in Harvard Business Review.

But faced with enormous amounts of information and decisions, leaders can confuse strategy with productivity, or spend too much time thinking without taking action. That's decidedly not strategic thinking. Below, see how Tasler deconstructs three prevailing myths about the concept.

Myth: Being productive is strategic.

Tasler says that many leaders confuse productivity with strategy. "Productivity is about getting things done. Strategic thinking is about getting the right things done well. The corollary of that truth is that strategy requires leaving some things undone, which stirs up a potent cocktail of unpleasant emotions," Tasler writes. When you have to set aside a seemingly important project, you will feel a loss of confidence and control. If you're eliminating an employee's department, you'll have to deal with "social pain and rejection," he writes. "The problem is that productivity is strategically agnostic. Producing volume is not the same as pursuing excellence. Without a strategy, productivity is meaningless."

Myth: Your job is to label what's important.

Tasler writes that labeling things that are important and not important is essentially an impossible task. Try out this exercise, which Tasler uses with Fortune 500 companies: Write down every project and initiative your company is working on and cross out each one that's not important. "If you're like 99 percent of teams, not one project on your list will get crossed out. That's because every project your team is working on is 'important' to someone somewhere, somehow," he writes. "They all 'add value' in some vague way. That's why debating about what's important is futile. Strategic thinkers must decide where to focus, not merely what's 'important.' Strategic leaders must consciously table some 'important' projects or ignore some 'important' opportunities." If your company is completing important projects on a first-come, first-served basis, that's not being strategic. A strategic leader will decide which project will contribute most to the company's mission, and focus on that.

Myth: Strategic thinking is about thinking.

Strategic thinking is something of a misnomer, because the term is missing the most important part of the concept--strategic action. Tasler says that thinking always must be followed by a decision that can be executed. "Ultimately, strategic thoughts must yield strategic action," he writes. "In spite of the uncertainty, complexity, and the ever-present possibility of failure, a strategic leader must eventually step up and make the call about what the team will and will not focus on."