Coffee is most often used for
Coffee, black gold, 'poison of choice'. Whatever you call it, it is the world's second most popular non-water beverage (second only to all forms of tea combined) and consumed world-wide.
Coffee can be seen as a nutritional product as it is a mixture of many nutriceutical compounds that all have individual purposes. Coffee can also exert effects like any supplement or drug and rival some of them in potency. It is not just an inert food product, coffee is a supplement.
There are benefits associated with chronic caffeine consumption, and there are benefits associated with acute caffeine consumption that fade with tolerance; if you like the latter, cycling is mandatory. If you like the former, cycling is not needed.