As far as I recall, that's actually a quote: „Kein Plan überlebt die erste Feindberührung.„ by General Moltke. Your translation is exact.
Just wanted to add a source: https://en.wikipedia.org/wiki/Helmuth_von_Moltke_the_Elder
Just wanted to add a source: https://en.wikipedia.org/wiki/Helmuth_von_Moltke_the_Elder