I was in Army logistics. Moving a tank half way across the world is complicated. It is not just packing up a single piece of equipment and putting it on a ship. The support materials for a modern main battle tank are about 3x the mass of the tank itself, and that doesn’t count fuel or more importantly people. Transferring to another country including training takes time. US tank crew train for 2 years. None of this is anything you want to rush. Only a moron would send ill-equipped and untrained personnel into a war zone driving a multi million dollar piece of equipment. Thankfully it seems all those people work for Russia