My take on it wasn’t hard and fast rules more....etiquette? You would ask or expect someone who hadn’t tattooed you before to go straight in to visible locations (hands, face etc). It’s like an earning of trust or establishing a relationship sort of thing.
No not really, at least in western tattooing there where certain things you got for specific accomplishments. This whole idea of trust or relationship with the artist are all relatively new ideas. In the old days most tattooers did it as a second/side job. OR where carnies, sailors or tramps. Tattooing on the weekends or on pay day. The mentality was mostly "pick some flash, give me that money and get out."
If you want to talk about placement on the body and meaning and the like you would need to look at tribal tattooing. Like what you see in the Philippines or asian pacific Ex: Samoa, tonga etc.