Cheers buds, that reader was quite helpful.
Yeah makes perfect sense however have to had that it would be ideal if "mame" would be backwords compatible, but anyways thanks.
It would be quite the opposite of ideal if MAME were backwards-compatible with older ROM sets.
The intention of MAME is to represent the hardware as accurately as possible. Encouraging people to keep around flawed dumps of ROM chips that have since been redumped to correct bit-rot or half-size dumps would be directly harmful to both preservation as well as to people who actually use these ROM dumps to restore old arcade boards.
In the case of games where the ROM dumps were updated because of copy-protection microcontrollers being dumped, the games quite simply did not work
in MAME, or entirely lacked audio. They would have the appearance of working, but there would be flaws in gameplay ranging from minor bugs to significant deviations from the intended gameplay.
People moan when games don't work in MAME, sometimes due to copy protection not being correctly handled, then moan again when ROM sets change to include the actual programs running on these protection microcontrollers. This sort of have-your-cake-and-eat-it-too mentality on the part of users is really for the birds.