I'm sure you're right that there were some that predicted the war would take longer, and I'm no WWI scholar. I had difficulty hunting down exactly who thought

I'm sure you're right that there were some that predicted the war would take longer, and I'm no WWI scholar. I had difficulty hunting down exactly who thought it would be over quickly, although from what I remember from watching/reading about the war (for example I know it was talked about in at least one video of The Great War Youtube series), there were military and political leaders (non-German) that did seem to think they could end the war quickly.