One of the most damaging financial traits I see is stubbornness. The couple whose business hasn't made it out of the starting gate suffers from a serious bout of it. The business is not viable, yet they think changing course would be a failure.
Of course, you don't have to be an entrepreneur to fall victim to stubbornness. Have you ever made an investment that declined in value, then decided to "just hold on" until the price rebounded? That's emotionally rational: I just want to break even! But financially, it's stubbornly irrational. What does your purchase price have to do with the future performance of an investment? Absolutely nothing, right? If the fund isn't headed up, it's time to sell.
The same is true in real estate. What you paid for a home five years ago is irrelevant in the current market. If you want to refinance or sell, you need to accept the market value.
Stubbornness also causes problems for job seekers who refuse to entertain offers that pay less than they made at their last job. Digging in your heels doesn't guarantee that you'll land your old salary—but it almost definitely guarantees that you'll be job searching for a much longer time.
I am all for patience and resilience. But it is so important to evaluate moves based on current reality. Not what was true five years ago. Not what you hoped for a year ago. Not what was within your grasp six months ago. Letting go of the past can be the surest route to a better future.