Women are too conscious about the length of their hair. One inch shorter and your client would never return to you. When you are not given a free hand, by default you should assume that you are not to mess with the length of clients hair.
When hair is long, it might lack volume and shine. So do a proper inspection of the type of hair your client has. Generally any haircut looks good on silky hair. Although you need to keep in mind the volume since long hair when they are silky, tend to look flat. For curly or wavy hair, few haircuts are a strict no no. For example, short fringes on curly or wavy hair are not recommended.
Long haircuts are the cuts for mid back length hair or longer. This does not mean you cannot do these haircuts on hair slightly below shoulders. They are included in this section, because they look best on long hair. Although this might change person to person depending on the type of hair, height, face shape, neck, and shape of head of the person. Some haircuts are more suitable for Silky hair while some look great on wavy and curly hair. It totally depends on the judgment of the stylist on which haircut is to be done on the client.
Remember that practice makes man perfect and observation makes him wise. Each time you do a haircut; try to figure out which haircut would best suit your client. Try to form a dummy picture in your head of the final outcome and then go all snip snip 🙂 🙂