Well Italian products have always had a reputation of being finnicky. Australian troops captured well over 100000 Italian troops in North Africa during the war & they were definitly not impressed by their firearms. Incuding those straight pull bolt action rifles with the inner cam (actually a similar action to many semi-automatic & selective fire rifles, except no discharge gas was ported to work the bolt) & those Beretta machine-carbines with the tandem triggers - one trigger for single shots & the other for automatic fire. Which were descended from the Beretta submachine gun of the first World War, which many consider the first production machine pistol. They still make 'em today, but the second trigger is now for 3 round burst. Plus we mustn't forget the 'Kennedy' rifle, which Italian troops used to joke about by saying that if one was on target with one of these rifles they must be a real bad shot, because if lined up right they never hit home.
I know I'm generalising as the Beretta must have done something right to have won the trials to replace the famous colt M1911 .45 in US Army service. But then again the original Armalite AR-15 (M16) rifle made it into service & it was a real POS (not the later A1 & A2, which by then had their problems sorted out). But then again it never went through trials as extensive as the Beretta. As it was first only selected as a perimetre defence weapon by the US Airforce, then later the South Vietnamese started using them, then finally the US Army & marines. The funny thing is the Bitish had wanted to put their newly designed 4.80 'bullpup' rifle into general service, but the US rejected it as it didn't fire the official 7.62 NATO round. Then the Americans go & start buying Armalite rifles that fire the non standard .223 (5.56mm) round. Even though though there was a 7.62 NATO version - the Armalite AR-10.
Probably the firarms makers with the best balance of design, engineering, quality & reliability are the Belgiums (FN, the licensie of most of the Browning patents ***) & the Austrians (Styer, Glock, Puch, etc), who inherited quite a bit of German technology after both world wars. Also the Czechs have a very good reputation too - the reknown Bren gun originated from a design from the Czech Brno works. Hence its name which is a combination of Brno & Enfield.
***The Model35 (1935) Browning 9mm Hi-power (which was the predecessor of todays high capacity pistol with its 13 round magazine) was the only firarm in official service (in quantity) with both the allies & axis during WWII. As they were made in Belgium by FN & supplied to the British in limited quantity early on & later after Belgium's occupation they were supplied to Germany in large quantities. They were also made in Canada by John Inglis & Co & supplied in quantity to many Commonwealth nations, including Australia, Britain, South Africa, New Zealand & the Canadians themselves, during the war. Pundits agree that the Belgium sibling is the better pistol. Actually FN still supplies limited quantities to many Commonwealth forces, including the Australian defence forces.