If you're having to rely on the ability to walk away from a commitment (to a supplier, say), then that needs to be built into the contract initially.

In California (say), where the culture is 'built for failure', the contracts already embed that optionality - meaning that the pricing already has the possibility of default built in. Negotiating the same flexibility elsewhere should just increase the pricing. Just as offering gold-plated guarantees in California should reduce the pricing.