These messages are generally formal in nature and have the information about the unavailability of an individual and also the details of the person who can be contacted in his/her absence.
The auto-delete policy - which is optional - follows a piece of government-funded research on work-life balance, which Daimler carried out in 2010 and 2011 with psychologists from the University of Heidelberg. The company now trains managers to set a good work-life example, and encourages them to set aside time when no meetings can be scheduled. This is supposed to be a time when workers can concentrate on their job, or take time off for any extra hours they have spent in the office.

Yes, I phoned a dentist office late in the day for a reinfected root canal problem and got a cutsy “humphrey bogart” fake reply on their voicemail — I thought it was extremely inappropriate for a business office to use something like this. It was hard to find it funny, especially because while calling me “sweetheart” and all that, the message didn’t actually tell me when they might return my call (later that day? Next day? Next week? Never?) nor did they offer any options for emergency contact with another dentist.
The people who never change their holiday OOO message or only include half the information, if you’re lucky. I had one sent to me once that was along the lines of “I’m on holiday until August 12th and then again from August 24th.”