Do you think the passion _caused_ the success? I think his success was equal parts intelligence and determination ("passion"). It seems true to say that those

Do you think the passion _caused_ the success? I think his success was equal parts intelligence and determination ("passion"). It seems true to say that those two ingredients alone were necessary and sufficient. He could still fail due to a run of bad luck. But it's a pretty safe bet that if things start to slip downhill, those setbacks won't make him any less determined. If a person's passion springs from their success, then they'll be discouraged when setbacks inevitably happen. Paul's model seems better: (a) doggedly pursue (b) something you're pretty sure will succeed. It'd be hard to doggedly pursue something that you're not already passionate about. In fact, that pattern seems common. Drew had decided to commit himself exclusively to Dropbox before even applying to YC; Airbnb's founders flew to NYC every week during YC to talk to users; Watsi's founders would probably do Watsi whether or not it was a huge success; etc. In every case it seems like their passion was independent of their success, because none of them were willing to give up under any circumstances. That's quite a different situation than someone whose determination depends on a positive feedback loop of success.