Every animal does it and some more than others. When a human gets 75 years old, then that human will have slept about 25 years of his or her life. Sleep does not only refresh, it also has a lot of vital uses. Too less sleep on the long term demolishes your immune system, it doubles your risk of of cancer and plays a key role in wether you will get Alzheimer’s disease or not. In the short term it decreases concentration, attention and the ability to make good decisions fast. Two thirds of the adults in well-developed nation have less than 8 hours of sleep a day, the recommended amount. What fatigue means for a employee could differentiate substantially. Fatigue for a pilot who flies everyday with a full schedule is often more dangerous than it is for a painter who paints a painting. Pilot fatigue is the cause of 4 to 8 percent of all crashes. Pilot fatigue happens when the pilot is simply tired. The primary causes of pilot fatigue are a too full schedule and a sleepless night. A scenario could be that the plane’s engines stop. What should the pilot do? How can that pilot make a decision in that life and death situation when the pilot can barely keep his or her eyes open? Enough about jobs let’s talk about genetics. There is a small group of people from the same gene pool that can function normally like any other healthy person with just 7 hours of sleep daily. More people have a gene that causes them to need more than 8 hours of sleep daily than the other gene. Someone who needs more than 8 hours of sleep daily to function properly will have a really hard time being a pilot as the working hours of a pilot can reach a staggering 14 hours a day. Sleep is underestimated and so are the dangers caused by having a too small portion of it. I think that sleep needs to be prioritized by the employers or if necessary by the government.