Turning an idea into a product requires planning not only for success, but for failure, too. Having a backup plan is absolutely crucial because when “Plan A” changes -- and it will. The ability to adapt is absolutely paramount if you want to keep the momentum moving.

Of the hundreds of combat missions I went on as a SEAL, I can’t think of one that actually went according to plan. Not one.

Related: Planning Ahead: 5 Steps to Dominating in Business in 2014

Planning for failure is different than expecting to fail. The former allows a swift response to act when the unexpected unfolds and requires minimal effort to shift the “mental gears.” The latter, however, breeds negative self-talk, a toxic “never-will-be” attitude and a direct path to nowhere.

The business world has a self-selection process that separates entrepreneurs into three categories: those who will be, those who have not and those who never will. If you want your business plan to work then you must have contingencies built into it that enable your company to keep sailing when you hit turbulent waters. Consider the following six parts for a watertight plan (the business application is in parentheses):

1. Situation. Write out the elements that describe your current situation. In the SEAL Teams, this would entail factors such as enemy disposition (competitor response), location (market share), terrain (industry or competitive landscape) and civilians (non-customers).

2. Purpose. A clear purpose is what pulls you along when business hiccups try to push you away. Purpose can tug you along when all else fails, allowing you to endure even in the midst of uncertainty, challenge or conflict. Entrepreneurs know this, as purpose is the main driving force that compels them to swim upstream while everyone else “goes with the flow.”

3. Assumptions. Write out everything that you consider to be true about your challenge and then do the same for everything you believe to be false. Next, reverse each one such that each true assumption is now false and each false one now true. Finally, game time! Play the "what if?" game where you ask yourself questions such as, “What if [true stated assumption] is false? What would make it false? How would that affect my situation?” The intent here is to gather a new perspective by changing the expectations associated with the situation.

Related: What's That Behind You! Why Paranoia is Good for Business.

4. Resources and constraints. Whenever we planned a mission, we were limited by the amount of supporting assets and the capabilities of each one. Some aerial platforms just produced better products than others, which, in turn, influenced the information we received and our ability to decide and act. Suppliers, employees, money, time and logistics must be constantly balanced to ensure your business not only has sufficient support, but that each player has current and accessible information that allows for timely decisions to be made. Apply this consideration to your list of assumptions.

5. Timeline and feasibility. Based on enemy (competitor) location and the terrain (industry), our timeline for getting to target (market) varied. Sometimes, a thorough analysis of the situation revealed that some places just weren’t feasible for us to reach, in which case we needed to revisit our purpose. If the threat to your business is too great, don’t be the entrepreneur trying to fit a square peg in a round hole. Sure, it may eventually go through, but it won’t look pretty in the end.

6. Course of action (COA). After running through the above considerations you should now have a clearer idea of likely and unlikely courses of action to take regarding your stated challenge. Now it’s time for you to decide on the best COA that addresses your challenge and fits your mission, resources, constraints and timeline. Call the best course of action to follow “Plan A” (or something more creative, hopefully), and use Plans B and C as contingency plans in case “A” doesn’t pan out.

Situations always change, that’s just the nature of the game, but purpose never should. Purpose is unwavering and is always to win. Don’t be afraid to change course in mid swing if your entrepreneurial efforts aren’t reaping the results you want. Remember, failure is just a temporary setback that becomes permanent only if you accept it.

Related: A SEAL Is Always Prepared: Finding Certainty in Uncertain Situations