From somebody that has been in the equipment repair business for many years, I wish customers would sit down and read the details of their warranty. It seems a lot of people have the mentality that if they break it then warranty will fix it. And in reality only about 1% of all failures are warranty covered repairs. I don't know how many times I have had customers bring in push mowers from a box store with a blown engine and the oil at the very bottom of the dipstick and then wonder why warranty won't cover their low oil failure and then find out that the mower came with the correct size bottle of oil in the box, but they only dumped in half. So instead of 18 ounces they only added 9.
Or bring in a trimmer that they purchased a week ago with a broken bump knob on the trimmer head and the manufacturer spells out in the warranty page in the owners manual that trimmer head parts are considered wear items and are excluded from warranty coverage, and then blame it on me because I can't warranty their new trimmer.