Hmmmm, my bet? My bet is lack of real world experience amongst the engineers, combined with a lack of "deckplate" level knowledge of the operators and who they are and how they do things. Seen this a lot these last few years. Engineers with no personal history in operating in that world and nobody who does being involved in bringing these things to the fleet.
"I know that they are used to doing things this way, and I know the widget we've designed will implode if used that way. But we'll just write in the book to NOT do that, and it will be fine.".
Case in point. "We'll design a rig that allows you to move the 90lb item across the fuselage on a rail, and a trapeze to hoist it up into the cabin for removal." Well, I'm here to tell you that if it takes 30 minutes to rig the rails, and 15 minutes to rig the 100lb trapeze, which takes a whole minute to hand crank the item three feet, sailors will put three guys down the hole and muscle that item across and bench press it up into the cabin. And they come back with, "Well, that's not whats in the book". If the sailor does not see any benefit, he's not going to use your gear.