Testing less means they can release sooner.
Here is a bad example. New game comes out. Graphical driver glitch crash. Typically would take 2 weeks to get to public as whole. Now with this they can release in 2 days to 10% fix up and release to whole by end of first week. So 90% of population got a fix sooner(1 week) And some percentage of the 10% may have had some annoyances. Sucks for them. But if they roll out in a way that minimizes this. It'd be beneficial to all overall.