Why can there be such glitches on the monitor?

Question

Monitors

Answer 1

How is the monitor connected?
Looks more like a crappy VGA cable or something like that

Answer 2

There can be many reasons.

1. Video adapter drivers:
   

   Try updating your system drivers.

   
   
2. The quality of the conductor (wire):
   

   The wire may be damaged.

   
   
3. Video card:
   

   The video card is gradually failing.

   
   
   1. Damage to the connector (socket) of the connection
      
   2. Gradual failure of the graphics core of the device.
      
   3. Other damage to the video card / video core
      
   
   
4. Monitor damaged:
   
   1. dead monitor pixel
      
   2. Physical damage to the monitor matrix
      
   3. Monitor connector (jack)
      

   POSSIBLE SOLUTION!!!: Try connecting the monitor to another device. If the problem persists, then the problem is in the monitor itself or in its connection.