Who's at Fault When You Follow Instructions?

I would estimate that about half of my inspections involve acclimation issues, including two this week. Maybe they would be more accurately termed "installed too dry" issues. Usually the situation involves flooring that has been acclimated per manufacturing or industry standards, are now at a reasonable moisture content, but are cupped. Everything else checks out normal.

When I ask about acclimation, the comments are that the flooring was acclimated per instructions. A third party usually confirms this. So I go find the instructions. I am surprised to see so many these days saying to not acclimate, or acclimate for 72 hours, or 7 to 10 days. Many instructions do say that the indoor environment needs to be in lived-in conditions. I thought acclimation involved getting the moisture content right. Is there a different definition?

My house is currently running 68 degrees F and about 32% RH. That's normal lived-in conditions for much of the U.S. at some time of the year. I acclimate my flooring for days or weeks (per instructions) in those conditions, install them, and they cup. And sometimes they buckle. And sometimes they get very noisy because fasteners loosen.

So if the installer follows manufacturer's instructions on acclimation and indoor environment, then the floors gain normal moisture and cup, who's at fault? Technically the installer followed instructions. Is the manufacturer at fault because the instructions are wrong? In my opinion, Rule #1: Follow the manufacturer's instructions doesn't override the laws of physics. I can't report that the flooring was acclimated insufficiently, but I can report that the flooring was installed too dry. Any comments?