Many amateurs believe that amateur radio is just a hobby and nothing else, and its prime purpose is to make many DX contacts on HF and to collect QSL cards, so why do you need to write an entrance exam for a hobby?
But in reality it is more than a hobby as it also provides a service to the public during disasters via Hamnet, or radio communications during public sports events.
The International Amateur Radio Union (IARU) is the international guardian of amateur radio and liaises directly with the International Telecommunication Union (ITU), as well as to innovate and advance amateur radio - and it is sponsored by amateur radio societies around the world including the SARL.
The real facts are that the amateur radio service covers a large range of activities where every amateur can find some aspect of it to enjoy, which also includes experimenting, research and pioneering in the very wide field of amateur radio science and technology all the way to the top end of the microwave spectrum. This is why the ITU refers to amateur radio as a service and not as a hobby as exemplified by CB Radio.
Do you think for one moment that the ITU would have allocated so many VHF, UHF, SHF and EHF bands of valuable radio spectrum to hobbyists?