A good cofounder is:
1. A pillar. This person is nearly impossible to replace because you trust them and they add incredible value to the team. It’s even more so if you’ve built a friendship and/or working relationship with them over time. Imagine starting from square one and going to a cofounder’s mixer.. I can’t.
2. Full of faith for the vision. They are not only motivated by the outcome but also by the work and the vision. They want to be a part of that vision because it’s something they fundamentally and philosophically believe in.
3. Someone who is not competitive with you. Many people start companies with their best friends, but sometimes this is exactly the wrong approach. Human relationships are complicated and someone you’ve known for years might seem like a good person to start a company with, that is until you start a company with them. Just remember to keep an open mind and that if you’re competitive with your cofounder, it probably won’t work out.
4. Someone you would trust with your life.
5. Complementary. If you have an idea they expand on that idea. If you’re a bit too liberal they’re a bit too conservative. Complementary should not be confused with diametrically opposed. There is such a thing as too different to get a long. A good example of a complimentary founding team would be the two Steves of Apple fame.
6. Unexpected. The cofounder should impress you. Not because they want to or are trying to but because you just happen to be impressed with the quality of their work/ideas/direction or whatever.
7. Challenging. They don’t blindly follow every word and they don’t challenge you on every point. They challenge you when you need to be challenged. After all, you can’t always be right even if you’d like to be.
8. Easy for you to get along with on some other level than just work. Either you have similar political views/principals or you both love Family Guy.. Whatever it is you should easily be able to find stuff to talk about. If you can’t even have a conversation with this person, they probably shouldn’t be your cofounder.
9. Someone who sticks around even when the going gets tough. Real tough. As I’ve experienced first hand startups are extremely trying for spouses, partners, friends, family and everything else. It takes its toll and no one can cross the finish line without paying that price. No one. You’re going to need someone who doesn’t just shine in the initial stages, they also need to shine when shit hits the fan and you’re losing hair, sleep, sanity and whatever else..
10. Someone who puts their money where their mouth is. You’ll know what this means when the time comes.. But the true test of character is when people start putting their own money into the project and they do it with both feet.
11. Well grounded with their ego. I’ve run into this one a few times. You obviously want someone brilliant to cofound your startup with.. But at what price? Some of the most brilliant people I’ve worked with also happened to be paranoid and/or kind of crazy. Not in a good way. Don’t go for the guy with 2 PhDs and the nobel prize in Physics just because his IQ is 270. You have to first make sure they fit into your universe and in a good way. God does not play dice with the universe and neither should you with your startup. Take that Niels!