When it comes down to it, mental strength can be even more important than physical strength. For entrepreneurs in particular, numerous articles discuss the importance of tenacity, "grit," optimism, and the ability to fail up, according to Forbes contributor David Williams. Mental strength can also be defined by identifying what mentally strong people don't do. 

Let’s share the list here along with thoughts on how each of these items is particularly applicable to entrepreneurs.

1.    Change is a scary prospect

People with strong mental faculties embrace change and challenge. People who are mentally strong will thrive in an environment of change and uncertainty. If they have a fear, it is not of the unknown, but of becoming complacent and stagnant.

2.    Spend time and energy on things that they cannot control

  People with a solid mentality generally do not complain (much) about traffic jams, lost luggage, or other people, as they are aware that all of these are generally out of their control. When they are facing a difficult situation, they know that their own attitude and response is the only thing they can control, and so they use these attributes well.

3.    Be Afraid of Displeasing Others

Do you know any people pleasers? Or, conversely, people who go out of their way to displease others in order to reinforce an image of strength? Both positions are undesirable. Those who are mentally strong strive to be kind and fair, and to please others as appropriate, but are not afraid to speak out. If someone gets upset, they can withstand the situation and navigate the situation with grace, wherever possible.

4.    Fear Alone Time

Strong-minded people cherish the time they spend alone as much as they enjoy spending time with others. Reflecting, planning, and being productive are the things they do during their downtime. The most important thing is that they don't depend on others to maintain their happiness and mood. People can be happy alone or with others.

5.    Give Up After Failure

Every defeat is an opportunity to learn and grow. Even the most successful entrepreneurs are prepared to confess that their early efforts always resulted in a slew of failures. Mentally strong people are willing to fail several times if required, as long as the lessons learned from each "failure" may help them achieve their ultimate goals.

6.    Get Results Right Away

Mentally strong people are "in it for the long haul" when it comes to an exercise plan, a food regimen, or launching a company. They are well aware that they should not anticipate instant outcomes. They put in measured amounts of energy and effort, and they celebrate each milestone and increment of accomplishment along the road. They have what is known as "staying power." They also recognize that true transformation takes time. Do you possess mental fortitude? Is there anything on this list that you require more of?

By Eleni Dimpetri