Need advice on evaluating a potential co-founder’s commitment : I will not promote

Hey everyone, I’m working on a startup with two other people, so there are three of us in total. We’re at the stage where we’re trying to get really clear about everyone’s role, commitment, time availability, and expectations before we go too far. There’s one person in particular where we’re a little unsure. Whenever we meet, we have good discussions and he seems interested and says he’s willing to contribute. The problem is that after the meeting, there’s usually very little communication from his side. If we agree on something, we often have to follow up ourselves. He doesn’t really proactively update us or push things forward on his own. I don’t want to jump to the conclusion that he isn’t serious. People have different communication styles and obviously have their own lives and commitments. But at the same time, if someone is going to be a co-founder, I feel like we need to know whether we can actually rely on them without constantly having to chase them. So I wanted to ask people who have actually built startups: How did you evaluate whether someone was genuinely committed to being a co-founder, rather than just being interested in the idea? A few things I’m specifically trying to figure out: - How do you determine whether someone’s promised time commitment is realistic? - How much weight should we put on their past behaviour vs what they say they will do going forward? - Is proactive communication something you would consider a basic co-founder expectation? - How do you handle someone who is interested but doesn’t naturally take initiative? - Would you give someone the co-founder title/equity upfront, or have them work together for a few months first and see how the commitment actually looks? - What kind of questions would you ask in a founder meeting to uncover these things without making it feel like an interrogation? - If someone can only commit part-time, when does it make more sense to call them a founding team member rather than a co-founder? I’m not looking for a way to “test” or trap the person. I just want to make sure that the three of us are being honest with ourselves before we make decisions around roles and equity. Would really appreciate perspectives from people who have been through this, especially if you’ve had a co-founder situation go wrong because of commitment or communication issues.