Beta reader

The beta reader steps in before the spelling proofread: their role is to spot what doesn't work in the structure or the argument (a chapter that drags, a confusing explanation, a title promise not kept), at a stage when it's still easy to fix.

For a how-to book or a guide generated with the help of AI, having one or two people from the target audience read the text before publication remains the best way to check that the content really meets a real need.