Comment # 43 on bug 1165780 from Franck Bui

IIRC this service is only useful when some BTRFS settings are changed somewhere
in /etc/sysconfig. That's the reason why a path unit is used to monitor the
relevant config file.

If so it seems there's no point in giving to the user the possibility to
enable/disable the service unit and start the service on each boot even if
nothing changed in the relevant config file, which is very likely.

At least I assumed that was correct since the maintainer accepted this change.

Regarding the use of After=local-fs.target, I think its usefulness was
discussed in the previous comments.