The cause of this is a known behavior of Unix/Linux scripts, but unfortunately not everyone knows this. If you change a script while it is running, the shell t

The cause of this is a known behavior of Unix/Linux scripts, but unfortunately not everyone knows this. If you change a script while it is running, the shell that runs it will read (what it thinks is) the next line from the old script, but it will be reading at the expected position in the old script file, but from the new script file. So what it reads and executes will probably not be what you wanted.