Just like any other component, your monitor can have a number of issues. Here are some of the more common ones:
A dead or “stuck” pixel is a pixel that has decided it’s done working. It’s black, and displays no color, or may be stuck with one color. There’s usually nothing you can do about these besides see if you can send your monitor back under RMA or warranty.
Many manufacturers will accept displays back with even a single dead pixel, other sellers require more than 3 pixels to be dead before they’ll accept a display back.
Sometimes a stuck pixel will just fix itself, other times you can run a short app to see if your screen can black the color back into the pixel. Some people have even had success physically pushing on their screens, though that’s an easy way to damage your screen and likely void your warranty.
What is ghosting? Ghosting is when response time fails. If your response time is on the lower end of things, then you’ll notice a blue behind objects as they move. This is the pixels of your display desperately trying to keep up with the rapid movement they’re being told to deal with.
Some people are more sensitive to ghosting than others. While some people aren’t even aware of it (or perhaps haven’t been exposed to a 1ms panel and seen a truly crisp media experience), others find it intolerable to deal with. What can you do about ghosting? Basically nothing, besides find a panel with a higher refresh rate.
When the FPS of some media exceeds the refresh rate of the monitor, it causes the monitor to glitch and try to display several frames simultaneously, the result is a screen-tear. It’s most noticeable while moving around in games and is easy to see around anything with straight edges.
V-Sync software limits your FPS to match the framerate of your monitor, to prevent screen-tearing, but v-sync has its own issues and limitations.