My guess is that it's not about quality but efficiency. Assuming the product works as advertised, someone might have pointed out that the power drawn is a lot more than the power supplied to the devices being charged (which to some extent is true for every wireless charger out there), and in a world where being sensitive to green issues is becoming the norm, this might have brought some bad press to Apple.

> Assuming the product works as advertised

The rumors are that it didn’t work as advertised, or even at all. Or when it did it could get hot and catch on fire.

I think Occam’s razor applies here.