I might have something of an answer. As a programmer, say you have a log file for activity recording purposes. When the server comes up, you check that the log file is there. If it isn't, you create a new one and the server is good to go.
But when the server is up and running, why check for the _existence_ of the log file ? You know it was created at start, so it should be there. You also have a tendency to foolishly assume that the people who will be administering the server have a clue and won't be deleting files willy-nilly.
Also, just recreating the log file and continuing operation is not really a good idea. If the log file disappears while the server is running, it means that there is a problem and it is actually better to crash the server to bring attention to it, rather than just trudging on and ignoring such an issue.