I teach web development courses to liberal arts majors, and the web server (Ubuntu Apache) is located in my office. At the beginning of each semester, I create public_html directories for each of my students and recursively set the permissions so their files will be served up correctly.
Every once in a while, a student reports permissions problems with a file she has uploaded. It is easy enough to fix this by tweaking permissions in Filezilla, but I have always wondered about the apparently inconsistent nature of this problem.
Possible explanation 1. I screwed up when creating the account and did not actually remember to recursively set the permissions.
Possible explanation 2. The uploaded file already had certain permissions attached to it that override the permissions I had set on the server.
Based on everything I think I understand about web servers, the first option seems far more likely. Is possible explanation 2 even theoretically possible?