It's likely that just like the differences in plastic quality there are differences in metals and metal quality. Craps, anyone?
Purchase from a quality manufacturer. Your typical Home Depot budget selection is not of high quality.
Thomas & Betts, Panduit, Tyton and Dennison are manufacturers of high quality cable ties that are used in various military and aviation applications. Products that meet Military Standard MS3367 improve your odds of getting a quality product.