I find this optical illusion - young girl or old hag - a good metaphor for inventive thinking. As an inventor you've got to be able to see both, old and new, in the technology you are trying to improve, disrupt, or displace. You need to understand how a recipe for success in the old world picture became a recipe for disaster in the new world. What are the useful features that you need to preserve in your future solution? What are the harmful factors that have to be overcome? If you don't the both sides of the innovation equation, the path to creative destruction can rather quickly become a road to self-destruction.