> One approach is value-based contracts: "we'll work with you and charge X% of the value we deliver."

Which still loses to the other bidders who say "$X in $Y months for $Z dollars".

No, not necessarily. It depends on how often and badly the org has been burned on past project failures.

Typically, the intermediate step is to tie some compensation (such as a bonus) to a particular metric, but why not just go whole hog?