Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Grinds beautifully, but the switch often jams

Though this grinder does a nice job grinding my coffee beans, the switch mechanism has little margin for error. About once a week, when I try to operate the grinder, the switch will not engage and the grinder will not operate. Only after I empty the beans out and give the machine a good shake will the lid finally go on tightly and the switch will engage. I am not particularly messy. This should not happen with a 3 month old coffee grinder.This grinder was a replacement for a seven year old Krups that I discarded due to the dullness of the blades (not surprising), but I never had a switch problem with that one, or the new Krups I bought for home. I regret not sticking with Krups.