Backups are hard to do because the reciprocal process of restoring data is complicated. A backup that cannot be restored is worse than no backup at all, since it has counterfeited peace of mind, with complacency. .
Amateur administrators may not believe that doing backups is difficult. Humans tend to contemplate the measure of backing up data as a worst case scenario, and experience psychological avoidance of the consideration.
Directory structure maintenance is required for sophisticated backup schemes, and incremental recovery schemes are challenging, while batch backups have problems of their own.
If a person has psychological avoidance of the concept, he will be especially easily deterred from undertaking a complex planning project. People tend to regard backing up as a matter of copying a file, scaled to large numbers. This is understood to be difficult, if one contemplates “all possible,” data restoration scenarios.