When I first started working as a manager for a group of folks, my own manager insisted that if one day someone in my group didn't show up for work and there wasn't a phone call or email or a note, he said to always try to get in touch with the individual to see if everything was ok. My manager was so insistent on following this practice so I asked him why he felt so strongly about this. He said he had an experience in which he had one of his folks not show up for work - no phone call, no email, no note so he tried to reach the individual by phone. After no response given multiple attempts to reach him, by late afternoon, my boss decided to drive out to the individual's house. When he got to his house, he found the gentleman passed out in front of his house. Thankfully, this story ended up with a happy ending.