The major reason to why the Italian people became disillusioned with the government was the economic situation. Not only was it a major problem itself but also led to consequences that followed which made things for the government worse as they failed to amend the problems. The war was expensive for Italy, the cost of supplying its soldiers with food and equipment necessary was proven to be a very expensive task for the treasury, so Italy had been forced to borrow large amount of monies from its allies. This meant the debt that Italy was facing had dramatically risen from the years 1914-19. Despite all this borrowing, it was still not enough and Italy began to print money, which quickly led to inflation. This scared Italy as prices increased as much as four times, and wiped out people's savings Everyone was affected by this from the poorer people to the middle classes, wages were not increased with the prices and land-owners were hit hard due to their reliance on rent. Industrialists, on the other hand, had fared relatively well during the war as what the government needed for the war was paid for by them. However at the end of the war there was no need for as much weapons, and government cut back spending due to debt, which led to a unwillingness for the industry to take on new laborers, and many soldiers returned to unemployment which became a disaster for the country as by November 1919 2 million were unemployed. This led people who had a distaste for their conditions to joining socialist trade unions and organising strikes. The government's failure to act, affected everyone as the middle class lost their savings, the working class distrusted the government, which led people to socialism and other extreme factions.
Socialism began to rise, and was in direct correlation to the governments inability to take action. The socialist party became very popular after the war and many industrial workers joined it due to dissatisfaction with conditions and the poor economic problems. The socialists party of Italy were greatly inspired by events in Russia and planned for their own version of events, to overthrow the liberal government, and by 1919 it looked as this might be the case as they secured 32.4% of the votes and the the largest party in the Italian parliament. This was extremely worrying to the middle classes and land-owners as it seemed as though this socialist takeover was very possible when in 1919 a million workers went on strike. The government, much to the dismay of the nationalists, took no action as they believed that a blood bath would caused more problems and just waited out the strikes, showing their weakness. Many commented that the army could of crushed the uprising easily. September 1920 showed the weakness of the government again with their inability to act and their tendency to hope the problem goes away rather than deal with it.
Industrialists were in arguments over wages and occupied their factories. In days 400000 workers were on strikes. Giolotti, the prime minister at the time, was determined not to use violence and was convince that the problem would sort its self out. Even when it seemed as though the workers were producing weapons, no action was taken making the government look weak even though it ended a month later. This showed the middle classes that the government would not stand up and tackle socialism leading them to turn to someone else.
The right wing parties criticised the Liberal government due to their toleration of the socialists and allowing it to rise, but also due to what happened at the Treaty of Versailles which D'Annunizio described as a mutilated victory. At the Treaty of London Italy was promised significant gains in the form of land for joining the war but when the Treaty of Versailles came, Italy had felt that they got a raw deal as they did not get Fiume and other places. Fiume was significant as D'Annunizio led an uprising which again was unchallenged as the government did not want to appear as it was taking sides.
Other land such as former German colonies that had been promised to Italy in the treaty of London, when not given made the nationalists furious and blamed it on the weakness of the government which made people think that the war effort was in vain as there was no gain just mass economic problems and loss of lives.
These are the main reasons to why people disillusioned with the liberal government failure to deal with economic problems and control its problems and people. These failures led to its downfall and in desperation people turned to more radical people and parties on both side of the political spectrum, right and left, as they were promising action, something the liberal government rarely did, and quick fixes to problems that the liberals would hope just went away.