In addition to the methods of processing cocoa, there are also many different varieties of cocoa tree each with it's own flavor profile. In panama they are using a new variety (agriculturally new anyway) of cocoa tree called something like VH47, because cocoa was suffering from a horrible disease. This tree is not only resistant, but it's a prolific bean producer, the problem is the cocoa tastes nasty when processed the normal way. It needs to be fermented in the sun first. Even then, although the taste becomes pleasant, it's still very inferior to better varieties.
However, almost all of the chocolate you eat has at least 15-20% of this cocoa, otherwise quite frankly there would be a shortage of chocolate if it wasn't incorporated.
So, some cocoa when plain tastes bitter, some is naturally sweet (not chocolate sweet), some is bittersweet, some tastes like flour unless it's mixed into something.