The rule of thumb is that User Safety and Privacy trump everything else. This is further accentuated in Enterprise usecases.
Reliability is important but you may argue that when I search for sneakers, if I get slightly different but good results, user trust is not impacted. But if the feature or domain is completely falling behind competition, then quick iteration with a Labs like release (rather than general availability) is a less risky way to test the waters and continue velocity/innovation.