How long did it take you to get scripted interviews implemented at Monsanto? How long to actually figure out what the scripts should say? Did your data indicate that the interviews were valuable & if not, how long did it take you to get interviews removed from the hiring process? How much of your time did you devote to building work sample tests or work sample sales funnel devices (microcorruption)? This is at an organization where you had a fair bit of influence.

Now take a more normal organization where the hiring pipeline is guided by people who treat it either as a sales process or a regulatory one. Those people are given their marching orders by executives that either believe or want it to be true that employees are fungible and readily available. The actual resources are allocated by middle management that are already resource constrained (thus the need to hire) and the people doing the interviews have never thought about it being something they can apply engineering skills against. Its a hard problem...

Also, I suspect your marketing department might prefer if you never downplay how hard it is ;)