The Los Angeles Lakers famously looked at Mark Williams' physical and said it was not worth the assets they had agreed to give up for the former Charlotte Hornets center. The trade was rescinded and all parties involved had to awkwardly return to where they came from.
Dalton Knecht, Cam Reddish, a 2030 pick swap, and a 2031 unprotected first-round pick proved too much for Rob Pelinka to give up for that big of an injury risk. The major problem from there was that given this trade was made at the deadline, there was no time to renegotiate.