Italian -and German-designed and built accordions are widely considered among the best instruments available. Those designed and manufactured in China, while often a good value (especially for beginning players and others on a tight budget who want a new, rather than used, instrument)  are generally considered to be of significantly inferior quality.

Before purchasing any accordion, you should familiarize yourself with the reputation and origin of its brand name. I have noticed that a number of the new accordions for sale or auction have Italian-sounding names such as Morelli, Rosetti, and Sofia Mari--none of which are Italian made or designed accordions, they are Chinese. Moreover, some of the sales ads featuring these accordions explicitly use the word "Italian" or "Italian Style" in their advertisements.

Again, there is absolutely nothing wrong with purchasing a Chinese accordion--if that is the instrument you are intending to purchase. If your intention is to purchase an Italian accordion, and you are looking at any of the brands mentioned above, then you are mistaken.