Wow! We've been using this kind of brush for decades. I guess we're lucky that nothing happened. I think, though, with proper brushes, none of the bristles come off.
I would imagine that over time even a proper brush could be weakened such it would be prone to this problem. Most of the bbq brushes i see are not exactly new.
it's metal. any sort of hypothetical shortcoming in manufacturing process can also be achieved through enough use, especially in a hot environment like a grill.
