Medication carries a risk.
One of the most important questions you can ask your doctor is "what happens if we just do watchful waiting?"
Taking meds, with their potential risk, if they provide no benefit is a bad thing.
While ADHD is real and needs treatment some of the people being medicated either have other diagnoses or they have bad parents. This isn't something that should be passed onto the child ("there is something wrong with you, take these meds") when it is the family that is broken ("I need to learn some better parenting techniques; we need to set firmer boundaries").