Google the term "buyer's guide," and you'll find...a whole heck of a lot of buyer's guides. Not a lot about the the history of buyer's guides, or the evolution of buyer's guides...just buyer's guides. For horses, AM radios, and yo-yos...just about anything.
It looks like no one knows where buyer's guides came from, not even the trusty Wikipedia. All we know is, they're here. And...they need help. A perfunctory look at a few buyers guides will reveal an almost-universal crater of functionality and technology. Why can't the yo-yo guide ask the user if they want a classic, flared gap, or modified shape and let them choose? Or, why can't the guide ask a question like: Are you looking for a yo-yo to perform looping tricks?