This was a fiery debate I heard where recently a person was venting on how when he talks to a lot of people who dream of working in a specific field he finds it crazy that people would label themselves as a professional in any sense when they have never booked a job yet. For example, imagine a computer repair business or start up photographer advertising themselves as professionals where they have never gotten one job as of yet.
This got reactions from people saying how there is nothing wrong with that as if you believe you offer something at a high level service with the knowledge as well then you should. Not only from a marketing point of view but as well psychologically if you believe you are an “amateur” per se then that can usually come across to people.
My view for this would be there is a difference between saying you are a professional in the sense of your skill and results versus lying on a resume that specific work was for some kind of top tier client. One of them is more about projecting your guarantee and work ethic versus the other is more of misleading gimmick I feel. I don’t think you necessarily need to book something before you can say you offer professional services as an example. Otherwise if you think about it the idea of hiring a certified professional should be null and void if that is just based on an education and not real clients.