What is the black mark after the texture?

Question

Iron

Good afternoon
I purchased a LG 24mp59g monitor.
I noticed that when the picture is shifted, for example, when the camera and sight move in FPS or scrolling through the tape in VK, the objects remain like a shadow for half a second. I tried to catch it on camera, you can barely see the outlines (there is no black frame on the picture itself). I got into the monitor settings, there I switched the "response time" option from "accelerated" to "fast". All problems are gone. But all the same, for the general development, I would like to understand what it can be connected with.
Computer config :
gtx 1060 6 gb
i5 8600k
16gb ddr4 3000mhz

Answer 1

Just the same with the response time. Faster pixel switching causes artifacts. For gamers, reaction speed is more important than picture quality.