I did not think it's true but many people seem to think like this. If you want to have a workpermit you hire the 4 Thai. If you don't have the 4 Thai staffmember you only own the company and get the business visa and not a workpermit.
Ah The Non O-A visa is for 50 years and older right? I ask this question because my friend told me that you can start a business in Thailand without hiring the 4 Thai people. And you only need to hire the for Thai people if you want to have a workpermit too?