From my point of view I think.
NO contract is worth it to be set up for long term.
Things can change daily. And there it does NOT matter who you ask.
Imagine, you make a long contract with someone for a certain service. Now you are stuck with the contractor.
Another one shows up and offers same service to way better conditions. But you are still stuck with the first contractor.
It's not worth it, imo.
People can make as much contracts as they want and also for the time duration they want. As long both parties agree with the conditions being made.
It has nothing to do with "who you ask", it only has to do with what the conditions on the contract are.