8 Common Mistakes When Choosing a Co-Founder

And what you can do to avoid them

Hey y’all — what’s been the most important decision you’ve made as a founder?

Most things in startups vary from company to company, but the answer to this is choosing your co-founder (or lack thereof) in most cases.

65% of startups fail due to cofounder conflicts, according to the Harvard Business Review.

It’s a serious and irreversible decision.

But what can you do upfront to avoid becoming a horror story?

I’ve seen the ups and downs of co-founder relationships in past companies and have more recently chosen the solo founder route for Megaphone.

Here are 8 common mistakes founders make when choosing a co-founder:

8 Common Mistakes When Choosing a Co-Founder

Optimizing for Skill Gaps

Wait… what?

Don’t you want to work with someone who’s good at the things you’re bad at, and vice versa?

Yes, of course.

But because this advice is so common (and obvious), I’ve noticed a lot of founders over-optimize for it.

You’d be better off optimizing for ambition gaps.

At a startup everyone is going to need to pick up new skills, and those skills will map to roles and responsibilities within the company. Your initial strengths are only part of what your contribution and role will eventually be.

For example, maybe you’re an engineer and your co-founder is a designer but if you both want to learn about fundraising and be CEO then you’re going to clash.

Have a conversation where you map out what each of you wants to have done throughout the life and by the time you move on.

Not Setting Hierarchy Early On

Splitting equity 50/50 feels good and is often the right choice, but you need a way to make quick decisions when you disagree.

At my last startup we built a co-founder operating system to help with this, but you can probably initially keep it simpler than that.

The easiest way to do this is just by setting a hierarchy. Basically for decisions the CEO feels strongly about and has a reasonable argument for, they get their way. The speed you will gain will outweigh any hurt feelings (or even wrong decisions).

This is why the reference calls are so important — know who you’re getting into a partnership with from all angles before you give them this power.

Making a Quick Decision

When you come across an ideal that you believe can be venture scale with someone, your impulses will tell you to immediately start moving as fast as you can to capture the market before someone else does.

It’s so easy to allow yourself to use that as a reason to start working with whoever you discovered the opportunity with.

But, for all the other potential reasons on this list, this is the most common mistake I see.

There’s no scenario where, even if a competitor launched today, you’d miss your chance to become a massive company by taking a week or two to validate your decision.

Not Working Together on Something Else First

The most common advice here is to do a hackathon or build a small side project together. This is basically a “work trial” but for founders.

That tends to be the best way, but I’ll expand the definition to just working on something together. This can be planning a trip for mutual friends, organizing an event, or anything else that will require you to collaboratively make consequential decisions.

The more communication and coordination needed the better.

The more challenging the better.

The more stressful the better.

It’s best to get data on this quickly, so sometimes building a small side project together may actually not be the right choice.

Not Doing (Blind) Reference Calls

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