There is the example of the required lipids in parental nutrition not being approved causing baby deaths that could easily have been prevented. Eliezer Yudkowski writes about it extensively in Inadequate Equilibria, but some of it is also in https://www.lesswrong.com/posts/x5ASTMPKPowLKpLpZ/moloch-s-t.... It offers an explanation for why some issues that are easy to fix don't get fixed anyway.