A frequently repeated excuse for WWI germany is that Wilhelm II had expressed desire not to invade the west, but had been told by his military that it was too late to recall the trains. Apparently the guy in charge of the german army's logistics in 1914 wrote a book after the war to explain that not only could he have turned everyone back before the border had he only received a command to do so, but also included appendices with the timetables for doing so.

[my book with the reference is currently unavailable, but https://en.wikipedia.org/wiki/Schlieffen_Plan#Der_Weltkrieg suggests it might have been Groener, Das Testament des Grafen Schlieffen: Operativ Studien über den Weltkrieg (1929)]