How do you iron out the contributions in a company by 2 people?

A friend and I are considering forming an LLC, we are drafting an operating agreement that cites 50/50; however what happens when one does not contribute his share, whether monetary or not?

If it is 50/50 doesn’t compensation etc. get mandated by the operating agreement too?

Consider a two-man real estate brokerage start-up; we incorporate together, but I spend a ton of money initially and find that he is not contributing. Months later, we are doing good business, my expenses have been covered and there is a profit to dispense. If I put in all the money and effort, why should he get 50%?

PS: We’re trying to get this ironed out before we start the bis.

Many thanks!