Hope is not a plan of action. Leaders should never 'hope' that things don't go wrong. They should never 'hope' that the plan succeeds. Instead, leaders should be prepared for things to go wrong. A leader should anticipate problems, mitigate issues, and take steps to ensure plans succeed. A leader that is not prepared for crises is one that will panic, freeze, or just plain make bad decisions when things go bad.
How do you prepare? Before stepping into a role as a leader, spend some time daydreaming. Consider your prospective job or mission. Don't dream about the rosy parts of the job, instead spend time imagining the worst possible things that may happen in your role. What kind of catastrophes might you be called to wrestle with? What are the potential impacts of your failures? What kind of conditions can you find yourself in? In order to succeed as a leader, you must be mentally prepared for all of the crises you may face. You must be prepared for the most critical decisions, the most dangerous situations, and for the responsibility that comes with failure.
There are some leaders that operate on the premise of hope. They neglect training out of laziness or complacency and hope that it is never needed. They do not make preparations for catastrophe, and instead hope that it won't happen on their watch. They are not prepared for critical decisions, hoping that someone else will make them.
When I was in Afghanistan, we had to do a property book switch with a new unit that was taking over our area of responsibility. In order to satisfy the supply books, we had to turn over our battle-tested and trusty heavy machine gun in return for the machine gun that the new team had. My very competent security team leader immediately took the new-to-us machine gun and stripped it down for cleaning. He was shocked to find that the machine gun was still coated in packing grease and a month's worth of dust. Since the new unit had signed for the machine gun, nearly a month earlier, they had never cleaned the gun! In a combat environment, it is absolutely necessary to clean weapons daily at a minimum! My team cleaned the gun as best they could and test fired it. It did not work. We had to return to our base, through a hazardous area, with one machine gun inoperable. At the base, we immediately took the weapon apart, fixed it, cleaned it, and tested it before re-mounting it.
Amazingly, the new unit had traversed the same road many times earlier that month, armed with their inoperable machine gun. They had an eighty pound paper weight mounted on their truck as their means of self-defense. Sadly, the team leader was an officer who was woefully unprepared for his role. He allowed his vehicle crew to neglect basic preparations for combat such as routine weapons maintenance and organizing the vehicle load to make ammunition accessible (despite repeated recommendations from my security team leader). The young lieutenant seemed entirely unprepared for his job as a leader. He seemed unaware of the consequences for his failures, consequences that could cost him his life, or worse, others' lives. Luck smiled on them for the moment. They had not yet been engaged by the enemy. They had eleven months to go.
The lieutenant was living on the principle of hope. He hoped that the machine gun would work, he hoped that the enemy would not attack them, and he hoped that he would survive Afghanistan. I hope that he got smarter.