Life is full of surprises. You never know later down the road if you might want to add a partner to your business. We set up all LLC’s as Manager-managed, because it gives you more flexibility down the road. When you’re one person, it doesn’t really make a difference. You just sign everything on behalf of the LLC as a Manager or you can even name yourself CEO.
As your company grows, and you decide to bring on a co-founder or partner, it is helpful to have a division between the individuals who own the company (the Members) and the individuals who run the business (the Managers). Investors, for instance, don’t want to have to vote on the day-to-day running of a company. So they can be Members but not Managers. People are happier to give you money when no responsibility comes with it.