I recently had a client approach me saying two of the sites he owns were not working. Both sites appeared to have database issues. I contacted Inmotion Hosting via online chat where after a long wait (45 minutes), I was told that there had been an outage and many databases were lost. The tech said they should be able to restore the databases from their backups. Unfortunately, the InMotion backups were bad and could not be restored. I did have a backup that I made when doing updates on one of the sites so I was able to get that site running. The other database was completely lost.
While I do offer clients maintenance plan that includes backups, some clients think they do not need it as they can maintain the site themselves and that their host backs it up. In this case, that assumption proved completely inadequate!
So, if you have WordPress site, either back it up yourself or find a web developer who offers a maintenance plan.