Common-law performance
A material breach may justify suspension while remaining duties and possible cure are assessed. Total breach or further conditions determine discharge. Substantial performance can leave a payment duty with damages for defects. Express conditions can demand stricter compliance; this story has no condition making perfect paint a prerequisite to all payment.
Article 2 tender
UCC 2-601 generally allows rejection for nonconforming single-delivery tender, subject to the agreement and other provisions. Installment sales use a different substantial-impairment analysis. Rejection requires timely notice; acceptance and later revocation are different routes.
Give cure its place
UCC 2-508 permits notified cure within the contract time and sometimes a further reasonable period where the seller reasonably expected acceptance. Signal Hall additionally grants a definite extension. Beacon's used units and later inability to provide new conforming units do not establish an unlimited right to postpone.
Insecurity is not repudiation
A clear repudiation can trigger remedies before performance is due. Reasonable grounds for insecurity under UCC 2-609 permit a written demand for adequate assurance and commercially reasonable suspension; the response period must be reasonable and cannot exceed thirty days. Mere worry is not an automatic breach.
CHANGE ONE FACT
Change one fact: Beacon offers conforming replacements before the original delivery deadline and seasonably notifies Signal Hall. May Signal Hall assume the first defect permanently ends the sale?
A. Yes. A first defect always ends the contract.
B. No. Analyze Beacon's timely cure right and the actual offer.
C. Yes. No seller may ever substitute goods.
Answer: B. The perfect-tender slogan is incomplete without cure. A seasonably notified conforming replacement within the contract time can satisfy UCC 2-508. The story's failure to cure by its documented extension is a different factual result.
UCC 2-601 / UCC 2-602 / UCC 2-508 / UCC 2-609 / UCC 2-610 / UCC 2-612 / CACI (state-specific comparison)