Dorsey, Stone and Williams co-founded Obvious which then spun off Twitter, Inc. As chief executive officer, Dorsey saw the startup through two rounds of funding by the venture capitalists who back the company. On 16 October 2008 Williams took over the role of CEO, and Dorsey became chairman of the board. On March 28, 2011, Dorsey returned to Twitter as Executive Chairman.
As the service grew in popularity, Dorsey chose improving uptime as top priority, even over creating revenue – which, as of 2008, Twitter was not designed to earn. Dorsey described the commercial use of Twitter and its API as two things that could lead to paid features.His three guiding principles, which are shared by the whole company and through its culture, are simplicity, constraint and craftsmanship.
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