Slack’s economic model has a privacy downside for those not paying for the product. Only paying customers have access to their archives and the ability to delete old conversations. Non-paying users (who make up the majority using Slack) only have access to their last 10,000 messages. All the messages over that count are archived by Slack, but exist in an inaccessible limbo. To delete an old message, a non-paying team on Slack would need to fork over a credit card or close — and delete — their entire account. It’s confusing, so Slack set up a “Team Settings” page that any user can check to see what happens to their messages. “It’s hard for people to keep all this privacy nuance clear in their minds so we wanted to lay it out very clearly,” says Butterfield.