enjoy the coffee i drink. of course, ‘mediocre’ is an opinion that is incorrect.
Not according to many in the coffee industry. It's an actual rating by coffee buyers of the type and variety of the beans that Starbucks purchases.
Starbucks helped to develop that "West Coast" (sometimes referred to as Seattle) style of roasting the beans till they are almost charcoal. It makes for a very strong, burnt flavor profile and virtually guarantees that any regional or varietal nuances of a particular lot of beans is completely lost. It's one of the reasons they do so well in the "milk added" coffee products (lattes, cappucinos, etc.) - it helps cut the burnt taste.
Many folks still like that flavor profile, and in fact I used to like it myself, until I started roasting at home and learned what I had been missing. I used to think that only dark roasts were good until I found that many varieties of Arabica beans hit their peak flavor profile at much lower roasts.