Most Ukrainians will agree that corruption has long traditions in Ukraine - at least it has been a common tradition for several centuries already to give "a present" to an official as a gratitude for his/her service.Why then the issue of corruption is that sharp today?
In Stalin times anyone with power had to have ties to avoid being executed.
Since the 1960s corruption was used not to survive, but to make your life better. Using "blat" you got a business trip to a foreign country, a better TV or a car.
Since the 1991 Independence proclamation, the salaries in the public service decreased drastically. So the population understood it was a good idea to support the civil servants - to have special treatment of their issues. In 2008 most civil servants of the local government were paid the salary close to the state minimum wage - which was scarcely enough for food.
2010-2014 Yanukovych's corruption became overwhelming. His vassals lost any sense of proportion stealing and laundering everything. This was one of the reasons of 2014 EuroMaidan protest.
After hundreds were killed by Yanukovych's regime, Ukrainians expected new authorities to understand that new country's course must be clean of corruption - it would not be tolerated. Moreover, the Russian aggression in eastern Ukraine called for mobilization of resources to support the Army.
Unfortunately, the so-called "political elite" has completely missed the people's aspirations. Not only Poroshenko de facto blocks creation of the anti-corruption court, but also his companies supplied the armour for the APCs that was counterfeit, according to the "Nashi Groshi" investigation (http://nashigroshi.org/2017/10/24/prezydentske-kerivnytstvo-ukroboronpromu-zlylo-100-miljoniv-na-prokladku-menedzhera-poroshenka/).
While Poroshenko pretends to be a good president, he failed to mmet expectations of his voters. He truly cannot understand that people wanted his to be not "less corrupt" than Yanukovych, but impeccable.
in the time of war, any governmental misdeeds are felt increasingly sharply. Most Ukrainians having lost at least half of their yearly real income (compared to 2013) simply cannot tolerate corruption anymore.
