I recently had a related issue where I was explaining an idea I'm working on, and one of my mates were engaging in creative thinking. The other found something he could do: look up a Chinese part to buy. He spent quite a few minutes on his phone, and then exclaimed "The hardware is done!" The problem is what he found was incomplete and wrong.

So he missed out on the thing we should do when being together: talk and brainstorm, and he didn't help with anything meaningful, because he didn't grasp the requirements.