“At Toyota (like most other manufacturers), there are certain standards (safety, equipment settings, quality tests, etc.) which are determined and set by various professionals. The question comes up, how can Toyota trust workers to change such standards?

“Quite the contrary, Team members do not have discretion to change professionally-defined standards without the approval of highly regarded technical specialty groups who know the underlying  science. These externally defined standards become inputs to standardized work.” 

The Toyota Way 2nd Edition by Jeffrey K. Liker (McGraw Hill, 2021) p. 111.