What should I do if I want to hire a founding team member, but they want to be cofounder?

Most startups fail. It is in a twist of logic but what you need to focus on is not how to succeed, on your terms, but how not to fail, with a team.

Committing to someone who wants more out of the relationship than you’re willing to give is a sure way of seeding a future conflict (true of any relationship, no?). Presuming the vision, model, planning, and strategy alone are what makes one a founder is another.