>>507354915 (OP)There were structural problems with its military like with most fascist states. Because Mussolini's power depending on military support, he curated leadership that was ideologically loyal over leadership that was competent, which lead to systemic problems with leadership, discipline, training and organization.
Unified Italy was a young country and had nowhere near the martial experience or background that the other major powers of Europe did. They learned a lot of harsh lessons in WW1 but devolved in the interwar period due to the aforementioned issues with fascist leadership.
Their industry was decentralized in a lot of artisan workshops rather than in large-scale factory production, which meant that there was generally a shortage of heavy equipment to arm their formations. Since the italians didn't have any infantry anti-tank weapons, they relied on a woefully inadequate supply of anti-tank guns and self propelled tank destroyers to combat armoured vehicles. This left their formations serially vulnerable to being overwhelmed and overrun by concentrated armoured attacks
And lastly: Italy was fighting for the restoration of an ancient empire. Their ambitions were territorial, and mostly focused on the Balkans and on securing naval supremacy in the Mediterranean, to which they relied primarily on the Luftwaffe for air cover. The Luftwaffe, having already been beaten over Britain, was in a training and leadership death spiral by the time the mediterranean went hot and the naval situation there steadily deteriorated. This left the italian soldiers on the ground in an conundrum:
They were fighting to rule the seas and to rule the balkans.
But the balkans were won and Germany, not Italy, occupied Italy's territorial claims.
Now Italy was fighting for the Germans in Russia and in Africa, for the sake of a German empire, not an Italian one, against Germany's enemies and not Italy's. Why die for Germany when you aren't German?