I compared it to marriage (and yes, I am married) because when you start a company with someone, you're beholden to their weaknesses as well as benefiting from

I compared it to marriage (and yes, I am married) because when you start a company with someone, you're beholden to their weaknesses as well as benefiting from their strengths. For example, if your co-founder only has 3 months of living expenses saved up, well you've got a deadline to get more money. Plus in the YC-model startup, you're usually living in very close proximity with your co-founders, so you need to get along with them as roommates as well as partners.