While Donbas has historically been an important mining and industrial region, I've read that it has been in steep decline for many years. Due to low productivit

While Donbas has historically been an important mining and industrial region, I've read that it has been in steep decline for many years. Due to low productivity of the industries and the high cost of services for the aging population, it is seen as a net economic loss for whoever takes it. I've read speculation that this is one reason why the Kremlin resisted annexing Donbas for so long. (There were initiatives from Donbas to get annexed the way Crimea was, because they were tired of being in legal limbo, but the Kremlin refused.)