Don't confuse liking someone with being able to work with them

[JS Burnett]

The best partner I ever had was someone I respected completely but would not have called to grab dinner.

The worst were people I genuinely enjoyed spending time with who had no business being inside my deals.

Liking someone clouds your judgment in ways that are hard to notice until the damage is already done. You overlook the missed deadline because they are a good person. You explain away the vague answer because you trust them. You keep moving forward because the personal relationship feels like evidence of the professional one.

It is not.

Before you bring anyone into a deal separate two conversations completely. The first is whether you enjoy their company. The second is whether they have the track record, the follow through, and the honesty under pressure that your project actually requires.

The first conversation has nothing to do with the second one. Keeping them separate has saved me more money than almost any other habit I have built in over 25 years of doing this.

What is the most expensive lesson you learned about choosing the wrong partner?