It is often the case that it’s not a matter of if the Excel file is lost or corrupt, but when the file is lost or corrupted.
Excel has a robust file recovery system to aid in cases where files become corrupted. However, (accidentally) deleting a file with no backup copy will often require a complete rebuild of the file from the ground up.
If your file is essential to day-to-day operations, or you are planning on implementing a change to the file that could prove disastrous if not performed properly, make certain you have a proper backup of the file. Creating additional backups, both local backups and offsite backups, are a great way to have peace of mind when things don’t go as planned.