Someone may say that the simulators are very expensive to build. But simulation systems of all kinds are very helpful to practice using a very cheap and safe way.
When soldiers practice in a field in real situations, not using the simulator, they have to use lots of real weapons including bullets. They have to take much time for preparing their weapons before the start practicing and maintaining their weapons after the finish their practicing. So that, the actual practice needs money to buy weapons, has a risk to get the injury, and needs time to prepare and maintain weapons. On the other hand, they use simulator when they are practicing, they can retrench the expenditure because they do not need to buy actual weapons, keep the healthy condition because the danger is reduced to get hurt, and save their time because preparing and maintain weapons do not need anymore.
Another very important example is the athlete. Athletes have to practice every day. Some athletes can get wounded easily like a boxer and taekwondo player because of hitting each other. If they get a big wound, they cannot practice for a while. By the way, practicing in virtual world is good for athletes and helps to keep their condition good. A time schedule is very important to preparing matches to athletes.
Sometimes, people need a remote control machine like drones. High-performance drones and devices which use remote controls have to practice many times because some drones are very sensitive and need high technique to control. If a controller is not careful to control the drone, it will be destroyed when it loses the balance. People can practice safely without broken if they use simulators.
All practices are good for preventing mistakes, but practice using a simulator is much better to prepare many of activities in the financial aspects. Also, people can do iterative learning in the same situations. So, simulation systems of all kinds are very helpful to practice.