I see many comments criticizing Apple's QA and wondering how this defect was not discovered prior to release. The bulk of the comments seem to adopt a tone of d

I see many comments criticizing Apple's QA and wondering how this defect was not discovered prior to release. The bulk of the comments seem to adopt a tone of disbelief. I find that hard to believe. It would be illuminating to know more details about how development and testing worked for the Yosemite project. Was this a late change? Were there systematic blind spots in the test environments and test processes that made defects like this difficult to discover internally? Are we even sure that this issue was not identified internally? Etc.