In this guest post by Ron Blanford, Yammer Product Manager, he discusses how the company uses hypothesis-driven development to improve their products. The team recently overhauled their iPhone publisher to make it easier for users to post photos on Yammer. Despite initial disappointing results, they decided to ship the feature as they believed they had created a better experience and refactored old code. This case highlights the importance of being data-informed but not completely reliant on data when making product decisions.