The 3-2-1 backup is a time-tested data protection and recovery methodology for ensuring that data is protected adequately and up-to-date backup copies of the data are available when needed. The basic concept of the 3-2-1 backup strategy is that three copies are made of the data to be protected, the copies are stored on two different types of storage media and one copy of the data is sent off site.
Scary stuff like this can happen to anyone:Importance of the 3-2-1 rule
The 3-2-1 backup strategy is recognized as a best practice for information security and data protection professionals. Although the process doesn't guarantee that all data will never be compromised in some manner, the strategy eliminates some of the risks involved in backup procedures. The 3-2-1 methodology is important in ensuring that there is no single point of failure for data. Not only is an organization covered if one copy is corrupted or a technology fails, but also if a natural disaster or theft occurs that wipes out the physical storage types.
https://arstechnica.com/gadgets/2023/05 ... mised/amp/
Your primary disk or the backup fails and you cannot recover any files. Imagine losing old photos of family and loved ones.
Always backup, backup, backup!!!