When he was selected by the neocon U.S. Assistant Secretary of State Victoria Nuland, Yats is the guy, the expectations were that Arseniy Yatsenyuk would be capable to do whatever the U.S. would order him to do in Ukraine.
But as Prime Minister of Ukraine Yatsenyuk was just a too small figure in a big game. The oligarchs still rule Ukraine and the great power politics overshadow any local politics. Even there Yatsenyuk was in way over his head. He never had real power in the parliament and the people of Ukraine hated him.
He was finally told to go by the same people who put him into his position:
KIEV, Ukraine — Arseniy P. Yatsenyuk, the prime minister of Ukraine, announced his resignation on Sunday in a surprise move that opened a new period of political uncertainty here.
…
Mr. Yatsenyuk and Petro O. Poroshenko, who became president, emerged as the nation’s most prominent political figures. But the revolution’s leaders soon turned on each other. [..] Ukraine’s Western allies eventually sided with Mr. Poroshenko and pushed Mr. Yatsenyuk to step aside.
Get hired by Nuland, get fired by Nuland.
The "good-bye" phone call Vice President Biden had with Yatsenyuk was lukewarm:
The Vice President thanked Prime Minister Yatsenyuk for his partnership during a historic time for Ukraine. He congratulated the government of Ukraine on its accomplishments over the past two years ..
"Partnership", "accomplishments" – I could think of greater words to express gratitude for the well paid, cushy job Biden junior was given in Ukraine. An abbreviated readout of the Biden-Yatsenyuk phone call would just say: "Don't dare to call me again".
Yatsenyuk is a good example of those who hope to ride to power on the back of U.S. regime change shenanigans. Such people are just expendable puppets to be put in the trash whenever their usefulness ends.