I'm having a hard time understanding the difference between self employed and NEO. They both do the work of an employee, with added administrative work, like yo

I'm having a hard time understanding the difference between self employed and NEO. They both do the work of an employee, with added administrative work, like you point out. But NEOs are about as happy and wealthy as employees, while SEs are less so. I couldn't find clear definitions for the two categories. I will note that SEs include contractors. They may have less admin work than other owners or SEs, but also less freedom and opportunity to innovate, and perhaps more cause to feel unhappy. Aside from that, I don't have much insight into non-contractor SEs, how they differ from NEOs, and why they're supposed to be less happy.