History books are filled with big decisions gone wrong. Napoleon's impulsive invasion of Russia that led to the deaths or desertion of most of his men. The disastrous launch of the Space Shuttle Challenger despite evidence that crucial o-rings wouldn't perform in that morning's freezing weather. In the business world, AOL's merger with Time Warner at the peak of the dot-com bubble.

Most people aren't responsible for decisions this big, but when you run a business, the stakes are anything but average. Do you focus on growth or profitability this quarter? Do you hire this candidate? Is that the right investment?

Decision-making is at the core of your job as a leader. And it's unavoidable: A non-decision, by letting something linger, is itself a decision (and very rarely a good one!).

Here are a few approaches that I've found can help a business owner figure out which decisions they can make quickly and decisively -- streamlining their approach -- and which should require additional deliberation.

Beware of biases.

We are all vulnerable to mental pitfalls which can at times lead to bad decision-making. These include cognitive biases. Everyone has biases -- they aren't inherently bad, but not paying attention to how they guide your choices is.

One example is confirmation bias, or our tendency to pay more attention to evidence that confirms what we already suspected. Another is group bias, where we tend to subconsciously favor people we see as part of our "in-group" -- like opting to hire a graduate of our alma mater over another candidate with similar qualifications.

The first step to overcoming biases is to be aware of them. Consider how you perceive situations and individuals. Stay cognizant of these as you frame the problem and work through the decision-making process, to ensure you are considering diverse evidence and viewpoints in as neutral a manner as possible.

Think small and fast, big and slow.

While many decisions are important, few are permanent. Many of the ones you'll make in the course of business are small, iterative and relatively easy to undo. This means they can and often should be made fast.

Be clear in your mind what the "big and slow" decisions should be. These have higher potential impact and are less reversible. Spend time on these. If a decision doesn't meet these criteria, consider delegating it.

Consider two decisions a business owner might need to make in a single day: Adjusting a script for her salespeople, and selecting the right candidate for a senior role. It would be easy to spend all day on either one, but her time is limited.

Since the script can easily be revised again if she makes a poor word choice, she makes some quick fixes and focuses her energy on evaluating the job candidates. That decision falls in the "big and slow" category, since it is less reversible, and could have more of an impact on her business.

Use tools.

You're probably familiar with making lists of pros and cons, or doing a SWOT analysis. Another tool to make decisions is an OODA loop, developed by military strategist and U.S. Air Force Colonel John Boyd.

This is a framework for iterative decision-making: Observe, orient, decide, and act, then repeat as needed. Observing and acting are straightforward, but here are ways to think about the two in the middle:

  • Orient: Essentially, ask yourself how you relate to the decision at hand. What might be affecting your decision? What biases and baggage might you be bringing to the decision? What other decisions are you trying to make right now? What's your current mood like? Do you have enough information to make an informed decision? Who needs to be involved in making this decision? Are they?

  • Decide: Consider using an issue tree, a tool that breaks down big issues into smaller components using a series of "why" or "how" questions. Each time you ask one of these questions, it leads to an insight that can then be evaluated on its own terms. A tree will progress from the key question to deeper analysis as you move to the right. 

No matter what type of business you're in, it's your job as a leader to influence decisions and to make the best ones possible. While instincts can help, it's important to recognize your susceptibility to biases that at times can lead to bad decision-making.

It's just as important to be thoughtful about how much time you're investing in a decision, based on its importance, and be ready to make a quick decision when needed.