Most often, the changes yield modest gains with minimal impact -- and that's the plan. "We're playing with peoples' livelihoods here, so it behooves us to be very careful," McKinley says.
Being able to improve business for the 800,000 craftspeople and small business owners that enable Etsy's existence is a motivator for employees.
"It feels really good at Etsy to be optimizing something that's not just about a corporation's bottom line," Thomas says. "The work we're doing, the ways that we're looking at data and using it to make things better, is all about helping the sellers on Etsy to be more successful."
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