NASA Erased Moon Landing Tapes
Write Protection was needed to save the data from destruction.
The year was 1969 and data was stored on tapes, but over 30 years later NASA admitted they erased those tapes with the original data. One of the biggest events in our history was erased from its original digital storage. Can you imagine that sort of thing happening today? Probably not, because we've got terabytes and petabytes of available storage in hard drives or solid state drives. So many ways to store data these days.
Another reason that would never happen today is because of a feature called Write Protection. Write protection is important to protect data on a master drive. This is very important to have in forensics, or bootable drives, or even in cases like NASA which holds very important top secret data. When duplicating a hard drive, sometimes the system you are using will modify the master drive even with a small change. It will not be noticeable to someone just looking at the data superficially through a computer, but it can be found when calculating the hash value of the drive. The hash value before and after installing into a machine can be affected, essentially damaging the master drive.
If you have sensitive master drives that cannot be altered, be sure to use equipment with write protection or write blocker. Using free software to duplicate through a computer does not offer this protection. Low cost duplication hardware also does not offer this because most consumers don't worry about a slight change. However, when it comes to professional applications, it may be necessary. This could be the difference of thousands to millions of dollars down the drain on a simple mistake by using a low cost solution to duplicate high value data.