Because, Martin Gibson, you wouldn't know a good guitar if it bit you on the ass. You have to rely on brand names that you know. If you were to walk into a music store and find a guitar made by a luthier whose name you didn't recognize, but that played and sounded twice as good as your Martin or your Gibson, you'd never know it. No ear. Just prejudice.

But stick with what you know. That's a whole lot safer than taking a chance on something that might by a lot better than what you have.