The repair command creates a directory whose name starts with a dollarsign (e.g., $tmp_repairDatabase_0), which is a Unix shell metacharacter. In case an operator wants to get rid of that directory for some reason (e.g., a failed repair or something), the consequences of failing to escape or quote that dollarsign can be maximally bad, e.g.,

rm -r ./$tmp_repairDatabase_0 # will blow away the contents of cwd
rm -r $tmp_repairDatabase_0/ # will blow away the entire file system

Ideally, no filename should ever include shell metacharacters. A trivial fix that ought to suffice would be to change the repair directory's name to start with something like an underscore.