When I taught employment interviewing, I would hand out to my students a job application that I'd printed off from Borders (the now defunct bookseller) and walk them through the different parts of an application.
When we got to the part about listing references, I always asked them the same question, prefaced with the statement: "Here's a lesson in following directions."
The reference section had three spots to list references, and it asked for the applicant to list three references who knew the applicant in a professional context and who had known the applicant for more than one year.
"What if you don't have three professional references who have each known you for more than a year? What if you only have one?" I would ask.
Students would immediately start shouting out answers.
"Leave the rest blank!"
"List your current supervisor!"
"Include someone who's known you less than a year!"
Once the din died down, there would always be one student who had been carefully reading the directions while everyone else was shouting.
"It says if you don't have three professional references who have known you more than a year, you can fill the remaining spots with people who have known you in other settings for more than one year."
What amazed me about this exercise was that even when I explicitly said this was a lesson in following directions, most people still didn't bother reading the directions about the reference section.
This phenomenon is by no means limited to college students. When I once served as assistant to a search committee, we had a weird application system that could only handle a single uploaded document as part of the main application. Thus, the application clearly specified that the applicant should save their cover letter and resume as a single document and upload them together.
Many people ignored these directions and uploaded only their resume to this spot, which meant I had to go digging through a separate part of the site to find their "supplemental documents" and then e-mail these to the search committee.
If the search committee hadn't had an assistant to do this work, it's likely most people's cover letters would never have ever been read.
It's a simple lesson, but an important one: Read the directions.