Mike Krieger of Instagram gave a thought provoking talk at the Warm Gun conference, sharing the design and product strategy process at Instagram:

In the end, Krieger wanted designers to keep in mind this simple question: are they getting their designs right or do they have the right design. What does this mean? It’s meant to focus on answering whether your product addresses a specific need and whether the market is going for it versus whether there is a market need, but people haven’t adopted it because of how it looks.