If Slack can dovetail seamlessly with how people behave, feel like second nature to use<br />and strongly appeal to employees, taking it away could become “like taking off your astronaut helmet in space,” Mr. Butterfield said.<br />Microsoft said users would embrace Teams because it had strong encryption<br />and global support and worked seamlessly with software they already used, like Excel.<br />“I’ve been building software for 15 years, and I’ve become more attuned to how the average person will interact with<br />and experience software in the last 18 months here than in the prior 13 years,” said April Underwood, who joined Slack as vice president of product in 2015.<br />The company behind it, Slack Technologies, found success by combining something<br />that Silicon Valley fetishizes — rich data on how people use a product — with something it often overlooks: How do people actually feel while using it?<br />The executives who run those businesses within Microsoft must “compete for budget<br />and mind share and attention,” he said, providing an opening for Slack to gain users while Microsoft managers wage internal wars.<br />“Building a product that allows for significant improvements in how people communicate requires a degree of thoughtfulness and craftsmanship<br />that is not common in the development of enterprise software,” Slack wrote in an open letter to Microsoft that ran as a full-page ad in November in .
