Instruct: Classify a given Amazon review as either positive or negative.
Query: Better quality control needed

These discs appear to be well made and they have done the exterior plywood (T-111 without grooves) paint removal/feathering job about as well as can be expected, however somewhere in the middle of the pack the discs didn't seem to have enough of the fuzzy hook and loop media on them and would not hold onto the backing pad. Some flew off after less than a minute of use. This continued even with replacement of the backing pad (but the new backing pad did help somewhat at least for a while). As a result, a lot of the sanding capability of the discs was wasted. This is doubly unfortunate because the ability of the Bosch ROS 20VS sander backing pads to hold on to sanding discs appears to be a weak link in otherwise excellent products. The hook & loop "grip" fades too quickly.