People only really believe what they feel they must believe in order to face daily life in the short term. Doubt is about the breakdown of this ability. Doubt is about alternative perspectives creeping back into the equation.
Where there is certainty, there is little thought, only faith. Such a situation is most certainly not conducive tio the development of a genuinely creative process. Surely the exploration and analysis of some form of doubt is what drives this process and is responsible for our ability (necessity?) to travel into uncharted waters.