Okay, another lesson I learned the hard way. People tend to like their own opinion more than your opinion. If they say you might be wrong, they usually want you to say, "Wow, that's a really, really fascinating point you bring up. I'm going to strongly think about that." Maybe not YCombinator, but like 99.99% of the rest of the world.
> As a word of advice to future single founders, they are going to aggressively push you the entire time. Be prepared to concede to them at some point even if they don't "get it." Otherwise, you will appear stubborn.
People need that. And y'know, you might be wrong. Or not. If you have a great reply, then maybe say, "You know, that's a fantastic point, I spend a lot of time thinking about that myself. Can I show you the numbers I ran on that?" Then show them, and say, "I still think about it. Do you think these numbers look good to go, or would it be worth considering more? What would you do about that concern, in my shoes?"
I'm going to keep the details vague here, but I remember one time I was selling something. The client wanted something else, that was stupider than my idea. But I was swallowed my pride and did it their way. Y'know why? Because I wanted their money more than they want my expertise. Oh, it was still a good deal for everyone. But they demanded it a certain way, and okay, you've got the money, you win, let's do it your way.
You wanted someone's money. Okay, they win, let's do it your way. Well, not that wishy-washy. But "I'll strongly consider that" (and then do! maybe even follow up on that point later with a few page brief/plan/strategy or something) is good. If you've already got the answers, stress how you think the other side is brilliant to bring that up, and you think about it and worry about constantly. Nobody wants to give money to someone that makes them feel stupid.
I don't know. Maybe this doesn't apply to YCombinator, they seem like the top 1% of intelligent and savvy people. But the other 99% of the world, definitely.
Edit: Once you've got a proven track record for doing massively amazing things, you can maybe just tell people how it's going to be and insist you're right. But that comes much later. If you seem like a commodity at all, you pretty much have to do it the way the people who have the money want it. When they bring up a concern, they really don't want it dismissed by some kid as not a big deal. Even if you're right (which you might not be).