Lack of standardisation on ANYTHING. I despise gadgets with a steep learning curve. There should be no need for it. As someone said, with the washing machine, "I want to wash clothes...I don't want to be a computer programmer." I don't have time for such "time-saving" devices. What are these designers thinking? If I want to snap a picture, I want to grab the camera...not the phone. Too many functions make an easy task difficult.
Next pet-peeve: WHY are good products discontinued? You spend hours or days locating a product that works perfectly. A year later, when it's worn out, just try to buy another one! They don't make them, anymore!