The answer is... Do this only when there's a problem.
There are two kinds of DBRs:
A regular or quick rebuild which is basically a reindex. This is done if there's some odd thing or two occurring that can't seem to be resolved.
Then there's the Extended Database repair, aka the EDBR.
When you run an EDBR, it does the same as a DBR but then goes further by deleting the cached files and validates content. This process can take a long time and sometimes can lead to further problems.
After completing either kind of repair, it's recommended to view Faulty assets. During the repair process, more so with an EDBR, content will be falsely marked as faulty. To clear the error, select view errors and warnings from the context menu after selecting the faulty assets.
