Russia has been at war with Ukraine for many months now, and has lost about 1500 tanks in battle... and the Ukrainians have been getting those back into the fight, against Russia

Ukraine’s own tank corps, 900 T-64s and T-72s strong back in February, also has suffered heavy losses: around 375 total write-offs, of which 130 or so tanks were captured by the Russians. 

The difference between Russian and Ukrainian tank attrition is that Ukraine has captured from Russia more modern tanks than it has lost to Russia, while Russia has had to dip into its warehouses and open-air tank parks in order to make good its own losses.

There weren’t enough intact T-80s and T-72s in storage to replace the T-80s and T-72s Russia had lost, but there were lots of T-62s. The Kremlin ordered the 103rd Armored Plant in Chita, in southern Siberia, to recondition 80o T-62s through 2025.

The old tanks began arriving at the front this summer, where they stiffened Russian battalions trying—and ultimately failing—to hold onto Kherson Oblast in southern Ukraine. There’s no evidence the T-62s played any meaningful role in the fighting. There’s ample evidence their four-man crews abandoned the tanks at the first opportunity.

https://www.forbes.com/sites/davidaxe/2022/11/28/the-ukrainian-army-captured-dozens-of-the-russian-armys-old-t-62-tanks-and-is-now-sending-them-back-into-battle/?sh=5c192ae618d2