First published in 2013, republished in 2020 with minor tweaks
I was talking to some folks about applying to Y Combinator and preparing themselves to found a startup more generally. One point that I found myself talking about, especially in terms of timing, was the two distinct emotions that I that many founders seem to possess, especially in the early days. 
They have an intense dissatisfaction with something in the world and an irrationally large sense of confidence about themselves.
As any founder will tell you, doing a startup is hard. Being passionate about the market you’re tackling, having a love for building great products — that’s all well and good. But when push comes to shove, there are few things more motivating than being a little pissed off.
When you’re mad, you work harder, you hold out longer, you move faster. You might be mad at the big players who are screwing over consumers, mad at your old boss who turned down your promotion request, mad at all the investors or media people who don’t get what you’re doing.
And that anger is fuel.
Paired with the anger is thinking you are the shit. To take the plunge and do a startup is to implicitly say:
It takes some cockiness to say that. Think about Steve Jobs, Patrick Collision, Anne Wojcicki  In their own way, each had a tremendous belief in themselves: their vision, judgement and abilities.
When I started Ridejoy, I had a chip on my shoulder, in part because the CEO of the startup I worked at once told me I was “a bit junior”. And yet he had dropped out of college to start that company and was the SAME AGE AS ME.
I’ve always had an unreasonably large amount of confidence and I did believe that I was better than other founders. Getting into Y Combinator certainly supported that thesis. 
By no means were these qualities “everything you need” to be a success. In fact, you’ll still most likely fail. But if you were thinking about making the leap and asked me if NOW was the time to start your company, I’d ask: “Are you feeling a little angry? And a little cocky?”
 Clearly this is anecdotal evidence — and yet our brain is wired to respond to stories and data of this nature. Take from it what you will.
 Same deal as  – correlation doesn’t prove causation, but sometimes it can suggest it.
 I say that at the risk of sounding like a douche, but I’m just telling the truth. When you’re in the top 7% of thousands of teams who apply to YC, you start to feel a little special.