What ultimately led to Italy leaving the paris peace conference?

The Italian Prime Minister Orlando didn't speak English, and as this was the language used by the other 3 members of the Big Four Allied powers, he felt left out and sidelined. It became clear that Britain and France were going to renege on the promises of territorial gains they had made to Italy in 1915 to get Italy to join the war on the Allied side. France and Britain had come to the conclusion that Italy had been more of a liability than an aset during the war - considerable aid in terms of arms and other supplies had been sent to Italy, as well as thousands of French and British troops, to prevent an Ital; ian collapse. Orlando thus wasn't held in very high regard by Clemenceau or Lloyd George. So really combination of these factors caused Orlando to walk out of the conference in a huff, feeling he and Italy as a nation had been insulted.