Averaging different economists' predictions makes sense. They each provide an x-y curve. Those curves average together in a mathematical way.
Product design ideas don't average together in this way. If one person wants to design a knife and another wants to design a spoon, and you average them together, you get a spoon with a sharp blade on one side, or maybe the blade is on the handle of the spoon, but either way, bad idea!! Or best case maybe you end up with a swiss army knife, in which case it's harder to clean, etc. Adding the knife feature sacrifices the simplicity of the spoon, which is extremely valuable.
Product design ideas don't average together in this way. If one person wants to design a knife and another wants to design a spoon, and you average them together, you get a spoon with a sharp blade on one side, or maybe the blade is on the handle of the spoon, but either way, bad idea!! Or best case maybe you end up with a swiss army knife, in which case it's harder to clean, etc. Adding the knife feature sacrifices the simplicity of the spoon, which is extremely valuable.