what were italy's consequences after betraying germany in WW1 and joining the allies which were Britain, France, and Russia

The Italians did not get what they believed they had been promised at the Treaty of London, and this resulted in animosity, which was exacerbated by the casualties Italy had suffered while fighting for the Allies in the war. In Italy, the administration was seen as weak and lacking in self-confidence.

Explanation:

During the war, the Italian government spent more money than it had in the preceding 50 years combined. The nation was practically bankrupted as a result of the war debt, food shortages, poor harvests, and huge inflationary spikes, with an estimated half-million citizens dying as a result.