What is a gimmick? Are gimmicks really negative to the industry?

[Ninja~Monkey]

I suppose in my own opinion a gimmick is what makes a device unique, like the Wii U's Gamepad Controller, The Xbox One's kinect and the PS4's... (someone fill in the gap there, I don't know too much about the ps4 yet). Anyway a gimmick isn't a bad thing, it's a good thing IMO. People are just tossing out the word like it's something bad, while I choose to see it as unique to the system or product. Surely some gimmicks are bad and some are good