In the year 2569, earth has advanced far beyond anyone in the pasts farthest dreams. Robots do all of the work, so people can choose either to not work or get a fulfilling career that they enjoy. Since they have 3D printers and whatnot, all items are insanely cheap, a spaceship with the capability to travel faster than light cost about the same as a Gerald Ford class aircraft carrier. Humans have made contact with about 90 other species, and interstellar highways of sorts connect them to each other.
Humans are pretty much immortal, as their brains can be saved on computers, computers billions of times more powerful than the most powerful supercomputer today. Humans are genetically modified before birth to be physically healthy, and are stronger, smarter and overall better than humans today. On planet earth, crime has been eliminated, and every person can expect to have a perfect happy life.
But, some people are just not satisfied with living perfect lives. Some people want to join spaceship crews to explore and etc. But in this world, finding gold and other riches doesn’t matter, as asteroid mining provides all raw materials. And space and land isn’t a problem either, as humanity has established colonies on other planets. So, my question is why would they choose to go into possible danger and death, when a perfect life is available to them back home?