Dying one's hair is something which maybe be done oneself or by professionals. Am I to understand that the construction of a sentence about hair dye is the same regardless of whether one does it to oneself or has it done by professionals? Are we left to infer which is the case based on how good the resultant hair looks?
I suppose this is similar in English wherein someone might observe "you cut your hair" as readily as "you got a haircut" but with rare exceptions (thinking of my brother circa age 4) intend to imply even in the first case that you yourself cut your own hair.