Thinking about backups after a disaster occurs can be expensive. Backing up your company data is more complex than plugging in a usb and copying the information, or installing a backup software. It’s important to have a backup plan, but it’s also important to have a recovery plan and test your backup. Without testing your backups, you are really just leaving things up to chance and hoping you’ll be able to recover when it’s needed.
Having 1 backup source is also not advisable, especially if you keep the backup media in the same location as the original data.