For some people it's enough to add hot water to ground coffee beans and get some kind of varying result.
However as people progress in their coffee journey they might start weighing the amount of ground coffee in relation to the amount of water, and then, one might argue that it's a slippery slope from there. Bean type, bean roast, grind size, pouring phases, infusion phases, blooming and the list goes on.

Brewtime is trying to strike a balance between the hardcore enthusiast who wants to track everything and the more average weird coffee person.
It is possible to track brews or beans or brews and beans together, it's up to you and what you think is helpful in your brewing routine.