I think the Ukrainian army and military were gutted during the Yanukovych regime and as a result were not prepared to deal with the crisis when it occurred, particularly in the NCO ranks. Also, then, at the most senior levels of the military, there was a large number of leftovers from the Soviet period, who have hobbled the efforts of the younger generation of officers to do their jobs.
What I heard at the colonel level, and sometimes even at the lower major-general level, is that they're all very competent. They're all very capable of taking on the Russian army, but they're not supported from above by the hangovers, and they don't have a sufficient NCO cadre to transmit their orders going down. That's a big problem, and they admit it.