I bought a cheap socket set from a discount store and it cost me more than the money
I needed a metric socket set for a small job on my car and grabbed one for fifteen bucks from a place that mostly sells party supplies. The chrome started flaking off the 10mm on the first use, and the next day, the ratchet just gave up and spun free. I had to stop the job, drive to a real store, and buy a proper set for sixty dollars. The real loss was the three hours I wasted, plus the frustration of having a tool fail at the worst time. Now I have a box of shiny junk that I'm too annoyed to even throw out. It sits there as a reminder. What's the worst 'bargain' tool you've ever been burned by?