Without retreading what other people have posted, I will comment on Perl coming from a Windows background.

When I started with Perl, I was trying to do account manipulation and managing file and directory structures. Most of the functions built into Perl were designed with a *NIX system in mind (for example permissions). In addition, the way permissions worked in WinNT were also more complicated than the standard *NIX version which ended up as a handicap; I had to depend upon the basic WinNT command line utilities; That said those utilities were pretty horrible to learn and use.

So one of the things that I learned Perl was focused upon *NIX systems when doing administration.

It also pointed out to me that Windows had serious limitations of its own. There were few toolkits that effectively dealt with administration and those that did were poor. I moved from thinking alot of problems I encountered with Windows were because of my ignorance to Windows was just a plain mess.