My first business—like many before and after mine—started in a bookstore. I spent several hours navigating through titles in the small business section looking for the secrets to starting and running a successful company. I walked out that day lugging no fewer than 10 books chock full of insights on business planning, marketing, sales, legal issues, accounting, and financial management. I was confident that I had everything I would need to succeed.

Almost 20 years later, though, I know that while those books provided a lot of important information, they were missing the piece I now know is the most critical to achieving small business success: how to manage the tough times.

Starting a business is hard. And writing the best business plan in the world doesn’t change that fact. My experience with starting both successful and unsuccessful businesses has forged my strong belief that a business owner’s ability to stay motivated during times of adversity is more critical to achieving success than just about anything else. Here are three things I wish I would’ve found in those books some 20 years ago:

Embrace a big vision
Cast a vision so big that even if you fail, you will have achieved something significant. Early in my entrepreneurial career, my “vision” was limited to building an incredible product, providing an incredible service, and, of course, making an incredible profit. I quickly learned, however, that a vision that small didn’t provide the motivation I needed to grind my way through the tough times.

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My very first rough patch serves as a perfect illustration. I was hyper-focused on building a fast-growing services company with the goal of exiting (and, of course, retiring) in five years. Things were going well. About a year into the business, though, I lost my largest client and faced serious financial issues. Since my vision was directly tied to my business’s success and my business was struggling, it provided no motivation.

That’s when I began casting visions that were significantly larger than my business. My current venture, for example, is driven by a vision to reinvent marketing so that small business owners have faith that their marketing will deliver the revenue they need to succeed. It’s related to—but not directly tied to—the success or failure of my business. Even in toughest of times, there are still things my business can do to advance that vision. That allows me to make progress during even the toughest times. And it’s that little bit of light that very often keeps me grinding until I’ve gotten through the storm.

Embrace the anxiety
While stressfully working on a startup about 10 years ago, a mentor introduced me to the concept of manifest anxiety. He explained that every venture goes through periods where anxiety reaches a level so high, people start to give up. He then highlighted the fact that anxiety comes in “periods,” meaning there’s a beginning and an end. He told me that all of the successful entrepreneurs he knew understood that concept in one form or another. As a result, they embraced periods of anxiety because they knew they would get through them faster. And, the faster they got through those tough periods, the less harm they would do to their business.

Every business owner goes through tough times that create extreme anxiety. I’ve faced many and will no doubt face many more. But getting through them as quickly as possible is critical to success, so why not embrace them by challenging yourself to see how quickly you can get through them?

Embrace the skepticism
Every small business launches with its share of vocal skeptics who seem almost eager to bestow upon you their list of reasons why your business won’t succeed. I’ve heard it all: bad idea, no market, not unique, bad timing, not enough capital—the list is seemingly endless. When you’re just starting your business, your enthusiasm will allow your own voice to drown out the skepticism. When times get tough, though, that’s not the case.

Early in my career, those voices wreaked havoc on my businesses. During tough times, they would cause me to question every decision, and ultimately slow my decision-making to a point where it was impossible to operate my business at the pace necessary for me to get through the most challenging moments fast enough to survive.

I’ve learned to use these skeptics as a source of motivation during the tough times. I carry their skepticism as a chip on my shoulder. Then, when the tough times hit, I use those chips as motivation to prove the skeptics wrong. Psychologists might say this method isn’t healthy, but it works for me. And, when tough times hit, you want to leverage everything you can to survive.