Since it's estimated that more than 90 percent of startups fail, grit is an enviable character trait for entrepreneurs who face inevitable setbacks as they build their companies. Grit separates the entrepreneurs who use failure as a reason to stop from the entrepreneurs who see failure as a stepping stone to something greater.

According to Angela Duckworth's bestselling book Grit, it is defined as "passion and sustained perseverance applied toward long-term achievement, with no particular concern for rewards or recognition along the way." This long-term focus is what separates many successful entrepreneurs from those who are most likely to give up, as a few of the core traits that make entrepreneurs successful include being future-oriented and motivated.

Since character is built on habits and establishing repetitive action, here are four practices that will strengthen your entrepreneurial grit, making you more resilient to setbacks and more likely to succeed in the long term.

1. Hold yourself accountable to short-term goals that contribute to the long-term goal.

Borrowing from Duckworth's definition, long-term achievement is important to our understanding of grit. Grit is about overall vision and an ultimate goal, rather than just shorter-term wins. But these long-term goals are more easily set than accomplished, as it's estimated that 92 percent of people actually never achieve the long-term goals they set for themselves.

One major reason? A lack of clarity on how to get there. It's important to create a roadmap that clearly outlines the long-term goals for your company (so you know what they are and what you're working toward), with the short-term goals required to get there.

These short-term goals must be both "challenging and specific." Researchers Edwin Locke and Gary Latham found that 90 percent of their studies saw higher performance when the participant was going after challenging and specific goals rather than vague or easy goals.

Entrepreneurs with grit don't shy away from the short-term challenges, and they're ready to make these sacrifices consistently to reach the long-term goals. Start by building a week-by-week roadmap to the long-term goal, and break down the smaller goals into challenging and specific pieces. If you need to, hire a business coach or strategist to help you get clear on these long-term strategies.

2. Avoid shiny-object syndrome.

Progress on a long-term entrepreneurial goal can be short-circuited when entrepreneurs get distracted. Shiny-object syndrome occurs when an entrepreneur continues to shift focus depending on new ideas or concepts that distract from the main goal. It can distract entrepreneurs from their current strategy to another strategy idea, or it can distract them from their overall long-term goal.

Since grit requires complete focus over the long run, new ideas or strategies cannot compete for your attention. It can happen easily, though, because the intentions behind shiny-object syndrome are always in the right place: You simply want to know that you're following the best course of action for your company. In fact, fellow Inc. columnist David Finkel reported that nine out of 10 business owners have struggled with shiny-object syndrome at one point in their careers.

If you're following predetermined specific and challenging short-term goals to accomplish your long-term business goals, you have to trust that you're following the best strategy for your business right now, unless you stumble across a pivotal realization that could launch your company into the stratosphere. Otherwise, subscribe to the "done is better than perfect" motto and keep on the path you're currently on.

3. Build your resourcefulness.

Those with grit embrace every entrepreneurial challenge with passion, are ready to be resourceful, and do whatever it takes to make their business work.

How can you make what you currently have work for you? How can you bootstrap, leverage relationships, or make a dollar stretch further? Well, you certainly have an email and a phone to make cold connections to build your business brick by brick. It's this daily devotion to the long-term goal that defines grit.

4. Learn from failure, but don't let it stop you.

Entrepreneurs with grit don't care about the statistics or chance their startup might fail, because they know they'll keep going even if failure occurs.

Our history's top entrepreneurs are proof of that grit. Milton S. Hershey was out of cash after two business failures when he started Hershey Chocolate. Sir James Dyson had 5,126 faulty prototypes of the Dyson vacuum cleaner before he built one that worked. Fred Smith, the founder of FedEx, was told that the FedEx idea was not feasible by his college professor.

Rather than letting a failure or setback be a reason to stop, follow in the footsteps of other entrepreneurs with grit and, instead, take failure as a sign that you're getting even closer to success.

Grit is built over many focused days. Continue to cultivate resilience, be smart about your short-term goals, and keep your eye on the long-term plan. By following these four practices and turning them into habits, grit will become one of your strongest character traits.