[tikhonj]

It doesn't have to be Python--you can use pretty much any language you want, so just use your favorite one be it Ruby or Python or Haskell or whatever.

I personally only use Bash when the script is just a trivial translation of commands I enter.

[Maven911]

sometimes you have no choice, such as working on telecom systems which have a stripped down Linux version running on it and there is no python/perl interpreter available.

[tikhonj]

That's certainly a possibility. For me, however, the vast majority of scripts I write will only ever run on my own computer or maybe also on some AWS instances. I suspect this varies a lot based on what sorts of things you generally work on.

[rhizome31]

Sometimes you could write in Ruby/Python/Perl but it's a good idea to make a shell script instead, so that sysadmins can understand it.