Why should I use a human readable file format?

Question

Why should I use a human readable file format in preference to a binary one? Is there ever a situation when this isn\'t the case?

EDIT: I did have this as an explana

Answer 1

They open the possibility to be created/edited with tools other than the original ones. New and better tools can be developed by others, integration into third party applications becomes possible. Think about binary iCal files, for example - would the format have been a success?

Apart from that: Human readable files improve the ability to debug or, for the savvy user, at least find the reason an error.