Even correct bug reports are a drain on your engineers' time and attention, and it frustrates power users to file them because being amateurs they often put too much effort into doing it.

Apple traditionally had a culture of a lot of high quality bug reports, but once those become too fast for anyone to keep in their head, there's no point to them because they'll just get lost. You might as well just go look for bugs if you run out of some. You'll find them.