[gimlids]

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.

[p4wnc6]

First, I did mention that when two things truly are mutually exclusive, it can be a reason for picking only one. Two designs that are entirely non-functional when combined could count as mutually exclusive. Even two designs that could be successful each on their own, but such that neither one could be created with 1/2 of the total budget, could be considered mutually exclusive.

I think you're pointing out a straw-man though. There are lots of cases where two ideas are not totally mutually exclusive, especially in design. And there are lots of times when the budget will allow you to explore building both designs in parallel and "investing in both" (thus diversifying your investment by not allocating the whole budget to only one project).

I agree when there is real mutual exclusivity you have to confidently choose one way to invest. I just think this is rarer than stated, and that lots of times you aren't actually forced to make that type of bifurcating decision, and so in general you should be eager to compromise more and more humble about not knowing which of the ideas will work, thus more willing to average over them, or divide up the budget and try multiple things.