Incorporating flat design and material effects does make the UI look subtle, its easier on the eyes, the open spaces depict a wideness in thought, the colours aren’t flashy and, don’t come in the way and its a breeze to interact with. But, these are just some design elements which have predefined ways of implication like material UI has its own set of guidelines. It is important to understand that for a UI, the priority of its look and feel is secondary and is preceded by the relevance of context. Sure, these must go hand in hand but what use will these beautiful elements be of, if the interaction seems to deflect from logic.