The amount and quality of information provided to your veterinary nutritionist determines the degree to which nutritional recommendations can be customized to your pet.
It's not quite "garbage in, garbage out," but for Vet Consults, it's "non-specific information in, generic recommendation out."
This is why Veterinary Nutrition Care has designed (and is constantly improving upon) the Nutritional History Questionnaire. It allows you provide all of the relevant information to your veterinary nutritionist without forgetting anything. Without this information, your veterinary nutritionist can't proceed with nutritional assessment and making a plan for your pet.