Have you ever had this conversation:
"I can't get this to work."
"Well, maybe they don't want you to do it that way."
Who are these "they" people anyway? Well, as we move through the world, often we are faced with things that we know were made by someone else. Ticket machines, electronics, websites, even doors. If they don't work as we expected, we often assume that the "they" behind that thing didn't intend for use to use them in that way. They didn't put that option in there.
Websites and interfaces are especially susceptible to this. I was watching a friend try to navigate a website the other day - he was evaluating a company that he might work for. He could not look at the company's employees by function, which meant that he couldn't determine who was in what department. "I guess they don't want you to know that," he said.
Was that message intentional, or unintentional? When you leave things out of your interface that users are going to want, are you doing that on purpose? Is it like the velvet rope outside a nightclub?
Or, did you just leave it off because you didn't think of it, and now people are taking away a message that you did not intend?
The things that are not there send a message, that says "That's not the intent here." So make sure you send that message on purpose. If you bury your "careers" link, maybe it's because you aren't hiring right now. But if you do want to be hiring, don't bury it. Put it right where someone new would see it right away.