Final answer:
A 2 person visual verification ensures the correct medication is being used and is correctly labeled on the field, to prevent medication administration errors.
Step-by-step explanation:
The reason for a 2 person visual verification of the medication/diluent bottle and cup on the sterile field is to ensure that both the correct medication or solution is being used (correct medication), and that it is correctly labeled on the field (correctly labeled). This dual check system is crucial in medical and pharmaceutical settings to prevent errors in medication administration, which could result in ineffective treatment or harm to the patient. The practice goes beyond tradition and provides a vital safety measure against potential dosing errors.