A debtor indicates he will pay 90% of what he owes, but is this modification enforceable?

The correct answer is based on the principle that a modification to a contract must be supported by consideration to be enforceable. In this scenario, the debtor's offer to pay only 90% of what is owed does not introduce any new consideration that would make the modification valid.

Consideration refers to something of value that is exchanged between the parties involved in a contract. A promise to perform an existing obligation is generally not considered valid consideration for a modification. Since the debtor is merely indicating a willingness to pay less than what is owed without offering anything in exchange, this modification is unenforceable due to the lack of consideration.

Others might suggest that the modification could be enforceable based on good faith or simply as an update to the contract, but these arguments do not stand up under the requirement for consideration. Similarly, a verbal commitment, while potentially binding in some circumstances, does not satisfy the necessity for consideration when it comes to modifying an existing agreement. Thus, the only viable reason for the unenforceability of the proposed payment reduction is the absence of consideration in the modification.