« Do not uncheck "Hide protect Operating System files (recommended)". There is no reason anyone needs to see them 24/7, even a developer »
It's always risky stating authoritatively that "there's no reason". Better to assume that you're missing some information.
In this situation, I want to see hidden and system files because I don't want to switch my entire system back and forth to figure out why the OS won't let me delete directories as
non-empty, when I see no files in them. If the OS wants to drop desktop.ini files everywhere, I'll get non-empty-directory warnings all the time. Sure, I can
guess that it's because the OS is hiding information from me (while at the same time warning me about things it won't show), but that's a fairly poor design. Windows software is also fairly random about what is considered "system" and which files should
be hidden. Add to that the fact that every application and service I install can also arbitrarily show or hide files from me, and you're going to get random fun mysteries to solve.
By the way, this is also how hidden and system files show up in version control, archives, copied directories, thumb drives (even when shared with other operating systems), and the
like: the OS can hide files from you, but it doesn't hide them from archival or other programs that simply enumerate directory entries. The result is that "special" files start getting copied everywhere, and can even clobber the actual system files in the
destination directories.
It's not just Windows, by the way. OS X also hides files that begin with a dot, which has also caused me huge headaches with version control systems and other directory manipulations.
I disable hiding on my Mac as well for the very same reason. Taking half an hour to discover this kind of surprise is something I refuse to put up with any longer.