Good ideas are ridiculously hard to find really and also extremely important. However most people with ideas don't have good ideas, and they can't recognize that their ideas suck so we tell them that ideas doesn't matter rather than the truth that their ideas suck.
Example of a good idea without good execution: Minecraft. Billion dollar product that could have been made by any half competent game engine programmer with some game designer friend. If anyone have an idea like that I'd love to build it, but they almost surely don't.
Um, Minecraft was executed very well. Maybe not as technically advanced as it could be, but Notch had a very good grasp on the player loop (you explore, you get resources, you build something..) and his artistic choices had a certain "poetry" (take now iconic creeper as a canonical example), which I think greatly contributed to the success of the game.
That idea was made by an extremely competent programmer. It was called InfiniMiner and it exactly fits the mold you've provided. Minecraft was then executed on it to an astounding creative success.
Ideas down stay consistent through the funnel - they are mixed with other ideas and formed into something else unrecognizable by the time they hit the bottom.
You just described Minecraft as being a brilliant idea, not a bad one.
Example of a good idea without good execution: Minecraft. Billion dollar product that could have been made by any half competent game engine programmer with some game designer friend. If anyone have an idea like that I'd love to build it, but they almost surely don't.