I heard that non-original games (VCD/DVD) are not good to continually play on hardware types such as a PS2 console - does anyone know why, and reduced life expectancy?
If you’re talking aboot burned games, they just don’t have the durability of an original (factory printed copy). But, no worries, you can make a copy of a copy for back-up. Try to keep the conversation as legal as possible. 
its usually because the dvd’s are of a poor quality to keep the costs low.