Twitter appears to be adopting a mindset of "move fast and break things", which includes testing in production. Some of the new features eventually turned out

Twitter appears to be adopting a mindset of "move fast and break things", which includes testing in production. Some of the new features eventually turned out fine, but they definitely didn't get everything right on first try. The Twitter before last year seemed more careful about changes that could disrupt users and businesses, as is appropriate for a company with millions of users. The current Twitter don't seem to mind as much.