What's the logic of going forward with an attack in spite of intelligence suggesting that either the target/objective of the attack was moved out of the area or resistance had been recently bolstered up that would make the attack more difficult?
Two examples from WW2:
- Pointe du Hoc - the US knew the guns had been moved but still pressed forward with the Ranger assault.
- Market Garden - the Allies had photo evidence that the Germans had moved heavy forces into the area.
Edit: This discussion is not limited to these examples, please add yours.