Safety, Security, and a sense of backup, especially for entry level new hires, where they're not thrown into the deep end without a life raft on their first day. Ideally pair lower level new hires with a mentor.
I mostly say this, because when I had an internship a while back, it felt like I was thrown into the black abyss as the only developer intern. The design and other interns seemed to get special treatment, but as a developer I felt completely alone and unsupported at that company.