Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Dangerous switch quality

I was thrilled to have my water heated so fast for coffee & tea. BUT this thermos would NEVER shut off. The auto off switch function never worked. At first I thought I'd just live with it, but then realized it might cause a fire someday if I forgot I turned it on. So sent it back to Amazon, even though I'd thrown away the packaging. So got partial refund without original packaging. Replaced with GE brand I found at the world's larges retailer Wmart. It is working PERFECTLY with perfect tasting water.