You don't have to be a smart ass to say that physical labor is available to everyone. Health and strength are important to maintain yourself in a state of doing physical work regularly. However, physical labor, as a rule, is always less paid than mental work, and here I think everyone understands that for some knowledge and development of specializations, education and skills are important. Trading requires the same experience and patience, and some mental analytical skills are necessary. In other words, physical labor, no matter how hard it is, is at the same time simple. Anyone can be a loader or sweep the streets, but not everyone can become a trader. Therefore, to achieve something, time is needed; those who are not ready to wait and learn choose physical labor.