Why did Pakistan order J-10C, not second-hand F-16s?

According to the Pakistan Institute of Strategic and International Affairs (HSIA), the Pakistan Air Force has signed a supply contract with AVIC to supply J-10CE (export-type, also known as FC-20) fighter jets. As per the agreement, the Pakistan Air Force will start receiving J-10CE fighter jets by the end of 2021 and eventually reach the delivery scale of about 36 aircraft enough for two squadrons. The Institute believes that the number of J-10CEs purchased by the Pakistan Air Force, especially the “36”, is mainly to respond to the threat of the 36 French Rafale fighters purchased by the Indian Air Force.