[IggleSniggle]

When you hire an engineer to build a dam, you expect them to consider piping and subsurface flows such that the foundation isn't swept out in a decade. No matter of the engineer was already paid, retired, etc.

My point isn't that we all need to make dams that can hold up for a century. The point is that you hire an engineer because you want someone with the judgement and expertise to apply the correct amount of engineering to any given solution. Over-engineering is on the pathway to correct-sized engineering. It's the experience, discovery, and exploration required to arrive at choosing what things actually do not need to be done.

When your manager asks you, "do we really need to do that?" It's the expert that can explain why it really is necessary, and the professional who accepts "we're not going to do that" as an answer. And if they still feel it would be harmful not to do it, then that's where professional duty kicks in.