Qualified rates are for qualified transactions, which are generally referred to card present transactions. “Card present” really means that you physically saw/swipe the card on device
Non-qualified rate apply to transactions that involve internationally issued cards (where card issuing entity is located outside the merchant account country or region), corporate, and rewards credit cards. There are also specialized transactions like eCommerce and over the phone (IVR), that fall into non-qualified rates (a.k.a. card not present transactions).