A product which is of incredibly low quality compared to its nearest competitors, yet maintains a similar price. The term originated from the tendency of such product to utilize colorful flashing lights (possibly in alternating or multiple colors) as a selling point.
Have you seen those cheap-ish third party controllers? Nothing but disco lights, they don't even have all the right buttons!
I got a new mouse, but it went bad after like a month. Stupid disco lights.
Sure this flash drive doesn't have the storage space or the lifespan as that other brand, but it lights up in blue, red, and green! I need some DISCO LIGHTS!
Man, fuck quality, I'm gonna buy some disco lights!