If you want to be an engineer /doctor you need a certificate from a university/medical school. The trust most of the time lies in the certificate. Yes, it may be necessary but in reality, very few people give importance to the certificate. But, to be a singer, writer or dancer you need a specific skill in that area and not a certificate. A singer must sing effectively, so the listener will just be mesmerized by the song. The listener must feel something. Similarly, it applies to any creative works. The creative work doesn’t require any certifications. But, the individual must certify their work himself/herself. Something which is creative cannot be replicated by someone else. Creativity cannot be stolen.