Reid Hoffman angel investor, Co-Founder & Executive Chairman LinkedIn and Partner Greylock & Ben Casnocha entrepreneur
Flickr is a popular photo-sharing website. Yet its founders Caterina Fake and Stewart Butterfield didn’t plan to start a photo-sharing site.
Begun in 2002 their original product was an online game played simultaneously by hundreds of players. “ the plan was to build  less [of] a game and more [of] a “social space designed to facilitate and enable play”” with features to attract users, including photo-sharing. When photo-sharing surpassed the game itself in popularity they had to decide whether to continue game development while expanding photo-sharing, or dedicate most of their resources to photo-sharing. They pivoted from the original plan to focus solely on photo-sharing. Its tremendous popularity resulted in Yahoo! acquiring it in 2005.
“ [its] evolution  “is a case study in smart adapting: its founders  tried many things to see what would work, and nimbly shifted their plans based on what they learned.” Reid Hoffman & Ben Casnocha, The Start-up of You (book), pg 52-53