was there some detail around what they didn't live up to in terms of their contract?
Wow. What a phenomenally bad deal that was for Yahoo and Marissa Mayer
Was it desperation - "If only we could put yahoo search in front of all those firefox users, yahoo will prosper again". Sadly I do imagine someone saying that. People who would disagree probably jumped ship a long time ago.
Bankruptcy or a new owner of your supplier may change their product so significantly that you want an immediate out without having to keep your side of the obligations. The supplier just restates with that clause that they won't change the product drastically and what that product is exactly is specified in the rest of the contract.