to playWhy do you have to use a mod or swap to play backup games?

PlayStation 1 particularly or really any game console...Why do you have to use a mod or swap to play a backup of a game? What keeps the console from playing the backup copy of the game?
There is a sign hash check on each game disc that you can't rip to an ISO that the to playconsole checks before allowing you to play the game. If it isn't there, the game console won't let you play the game. Same for PS1, PS2, Wii, Xbox, just about every console that uses discs. The mod bypasses this hash check letting you play backups. If you look at the bto playack of a burnt disc you can see visibly where the data has been burnt to, now try looking at a legit game disc, it looks a lot different. Common household people don't have the special burners to put that special hidden line of data on the discs.