Consumer advocate: The manufacturer’s instructions for assembling a product should be written in such a way that most consumers would find it much easier to put the product together if the instructions were available than if they were not.
Principle
The instructions should make it easier to for most people to put together the product than it would have been if they didn't have the instructions.
We could turn this into a conditional:
not much easier for people shouldn't write to assemble product with → instructions this these instructions than way w/o these instructions
Evaluate / Goal
This is a weird question stem. It almost feels like an Apply the Principle task, except it's asking "where would this principle not be applicable".
If we're looking for a situation in which the advice "can't always be followed", then we would want a situation where it's not possible to write instructions that make assembly easier (for most users) than it would be without any instructions.