Professional or something else?
If you go to a doctor or to a lawyer with some need or problem, you expect that - assuming he's both honest and competent - that he'll acquaint himself with all your facts, symptoms and so on - and then give you sound advice or treatment.
That is what entitles them to the title of 'Professional'. They are expected to have measurable expertise in medicine, or law, and are required to apply it properly, to an accepted, high standard. They have a duty to give any given patient or client much the same treatment or advice no matter which doctor or lawyer he consults.
Now, compare this to a person who specialises in building Japanese gardens for his clients and consider - how to measure whether the specialist in Japanese garden construction has, like the doctor or lawyer, the required expertise, and whether he has applied it properly?
It would seem, using doctors and lawyers as indicators of what it means to be professional, that - with minor differences - the garden client should expect a very similar result for his garden, no matter which garden specialist he consults. If he cannot expect this, does it place the garden specialist in an entirely different category - e.g. not that of Professional, but that of Artist?