 Victory in Normandy stemmed from several factors. German preparations along the Atlantic Wall were only partially finished; shortly before D-Day Rommel reported that construction was only 18 per cent complete in some areas as resources were diverted elsewhere. The deceptions undertaken in Operation Fortitude were successful, leaving the Germans obligated to defend a huge stretch of coastline. The Allies achieved and maintained air supremacy, which meant that the Germans were unable to make observations of the preparations underway in Britain and were unable to interfere via bomber attacks. Transportation infrastructure in France was severely disrupted by Allied bombers and the French Resistance, making it difficult for the Germans to bring up reinforcements and supplies. Some of the opening bombardment was off-target or not concentrated enough to have any impact, but the specialised armour worked well except on Omaha, providing close artillery support for the troops as they disembarked onto the beaches. Indecisiveness and an overly complicated command structure on the part of the German high command were also factors in the Allied success.
