Obviously the truth is messier than that, and it's worth noting that Drucker later recognised the toxicity of Management by Objectives and disavowed it. Quite a bit of OKR literature is devoted to avoiding it becoming its progenitor, MBO.
Worth adding that Deming (after Shewhart) recognised two kinds of variation: special cause (specific the work item in question) and common cause (an artifact of the process). That knowledge work involves a lot more of the former than does manufacturing does not excuse inattention to the latter.
> Drucker later recognised the toxicity of Management by Objectives and disavowed it.
Reminds me of a seminal treatise for Waterfall by Royce[0], where he basically says it’s fraught with issues, but can be coerced into something semi-usable. Not exactly a ringing endorsement. I think that paper is used as the template for all Waterfall work.
[0] https://dl.acm.org/doi/abs/10.5555/41765.41801