Contract law is designed to minimise:
- the cost of writing a contract;
- the cost of courts rewriting contracts;
- inefficiency (including behaviour) from inefficient, poorly written, or incomplete contracts.
Courts use and select the rulings that lead to the fewest exculpatory clauses. Doing so leads to contracts being as short as possible and feasible, and still delivering the necessary terms and conditions.
I have an old paper on some of such things here: