"Please tell us in one or two sentences about something impressive other than this startup that each founder has built or achieved."
"Please tell us about the time you, philwelch, most successfully hacked some (non-computer) system to your advantage."
"Please tell us about an interesting project, preferably outside of class or work, that two or more of you created together. Include urls if possible."
"How long have the founders known one another and how did you meet? Have any of the founders not met in person?"
"Please tell us something surprising or amusing that one of you has discovered. (The answer need not be related to your project.)"
The problem is that autobiography is awkward and weird to discuss. So while you may discuss ideas, that's probably so you have something less awkward to talk about in the process of feeling each other out as people. Discussing your ideas shows how you think and operate; telling someone how you think and operate is, OTOH, fraught with cognitive error and lies, since most people don't have an accurate self-image.
PG's goal is to make money. Period. It may give you the warm and fuzzies to believe that he's trying to find passionate people, but without a profitable idea, the rest doesn't really matter.
These questions matter because PG doesn't want people that don't work together well (which will cause unneeded drama and destroy the company internally), and that they will have the drive to continue on the current project and not give up (there are many people that jump around to 1000 different projects or give up easily). It's merely a way to increase his chances of ROI, which isn't a bad thing.
I don't think there's any dispute over why an investor invests. The point is that investing in people is a more effective means to that end than investing in ideas, that autobiographical questions are asked in the process, and that discussing the idea also functions as a way to evaluate a candidate as a person.
"Please tell us in one or two sentences about something impressive other than this startup that each founder has built or achieved."
"Please tell us about the time you, philwelch, most successfully hacked some (non-computer) system to your advantage."
"Please tell us about an interesting project, preferably outside of class or work, that two or more of you created together. Include urls if possible."
"How long have the founders known one another and how did you meet? Have any of the founders not met in person?"
"Please tell us something surprising or amusing that one of you has discovered. (The answer need not be related to your project.)"
The problem is that autobiography is awkward and weird to discuss. So while you may discuss ideas, that's probably so you have something less awkward to talk about in the process of feeling each other out as people. Discussing your ideas shows how you think and operate; telling someone how you think and operate is, OTOH, fraught with cognitive error and lies, since most people don't have an accurate self-image.