No, you do your development as a kid. Then you have success, compete internationally. Junior, Youth Olympics, Olympics, World Championships. If you’re a top amateur you might stay around for a second or third Olympics. You might go chase some scraps in the pro game, or you might keep fighting the best for the glory of your country. You obviously don’t know what’s going on. In the US there’s less of a focus on the amateur game, that’s because they’re not very successful and US culture is more about show/hype than substance. Educate yourself and maybe you too can start to enjoy the sport instead of the show.
Outside of Cubans who are forced to stay amateur by their backward communist system, how many olympians stick around for their 2nd and 3rd olympics? You have more and more top level former soviet guys going pro in their early 20s. British, American amateurs amongst other nations have always gone pro as soon as possible after a respectable amateur career. Asian and Central Americans fighters often dont even bother with the amateurs and go pro when they're in their teens.