When I pull the trigger the disc spins for a while then it stops, the mill hums like a transformer eating its coils then the disc spins again and all is well. It has a small rotary switch to adjust the speed. At the lowest speed, the grinder will not turn after a whirring noise. He just hums. It gives off that hot insulation smell when it's buzzing. I don't expect this case to last long. However, I don't need it for long. Long enough to remove some wall textures. Then I'm fine when I throw it in the bin and I'm happy that the texture is gone. As for the feature when it spins again, it's great. It blends in with that texture so well. The texture was laid with a thick layer of drywall, and then painted with latex paint. It's a terrible texture with big ridges and stuff that collects dust and dirt. Just awful. This sander goes through the paint and levels the drywall mix. And it sucks up the dust generated during sanding. Not all the dust, but the vast majority. I've used grinders on this texture and I know it generates an incredible amount of dust. It's nice when these things get sucked into the collection bag before they go all over the place. Yes, the grinder sucks and blows dust into a collection bag. A shop vacuum cleaner is not required.