...if you consider quality a lever, you're not the kind of person anyone should want to work with!
You agree on quality standards before you begin, and you deliver the quality level that you agreed beforehand, not more, not less (you deliver sooner if it goes better than expected giving the product-owner ability to add features or redirect effort actually using your "superpowers" if any to give the business a real advantage), at a profit or at a loss. Otherwise you're not a professional, you're either an amateur or maliciously dishonest/exploitative!
You could just as easily say that you agree on the feature set beforehand, and you deliver that feature set, not more, not less (you deliver sooner if you finish the features early).
"The quality level you agreed beforehand" is meaningless without some infrastructure and processes in place to verify it. And in practice, those infrastructure and processes are compromised at least as often as the feature set, the budget, or the timeline.
You agree on quality standards before you begin, and you deliver the quality level that you agreed beforehand, not more, not less (you deliver sooner if it goes better than expected giving the product-owner ability to add features or redirect effort actually using your "superpowers" if any to give the business a real advantage), at a profit or at a loss. Otherwise you're not a professional, you're either an amateur or maliciously dishonest/exploitative!