It’s a safe assumption that the vast majority of computer users today use LCD monitors. It is in fact a very reliable technology and it’s not often that you hear of one breaking. But being that it’s an electronic device, yes it will eventually fail.
How long does it take before an LCD fails completely?
Usually about 5 to 7 years.
What is the first thing to "go" on an LCD monitor?
With a free-standing LCD (i.e. one attached to regular desktop computer), the backlight is usually the first thing to break. With a laptop a whole host of other things can go awry. More on that in a moment. When a backlight fails, the picture will get extremely dim. It will still work but be almost unreadable.
Is it worth it to repair an LCD monitor?
Never. The cost of repairing an LCD monitor will usually cost more than replacing it outright.
Common issues with LCD monitors
Solid horizontal and/or vertical lines
One day you will turn on the monitor and these brightly colored lines will appear with no way to get rid of them. This is a hardware fault and there is no fix for this. Replace the monitor.
Monitor takes a while to "warm up" after starting it
You turn the monitor on and it takes a minute or two to reach full brightness. This is a backlight issue. You can still use the monitor normally until the backlight breaks (which it will eventually).
Monitor flickers on and off randomly
This is laptop-specific. The LCD ribbon connector cable is damaged from normal use of opening and closing the lid over time. This can be repaired. The monitor does not need replacement, but the ribbon connector cable does.
If you’re brave enough you can order this part from the OEM manufacturer and replace it yourself. It it normally located under the left-side hinge. It is not easy, but certainly cheaper than replacing the entire display.
Suggested course of action is to locate an authorized computer repair center and have them replace the ribbon connector. It will cost anywhere from $60 to $150, labor included. This may sound expensive but it’s still cheaper than replacing the monitor itself which will cost a whole lot more.
Corners or one side of monitor appears dimmer than the other
Again this is a backlight issue. There is no fix. Deal with it or replace the monitor.
Everything "goes green" or "goes pink" or "goes red"
For laptops, again this is the ribbon connector cable. Replace it. For desktops, replace the monitor cable which may or may not fix the problem.
"Wild patterns" appear for no reason
It will look something like this:
No fix for this. Monitor is busted. Replace it.