In brief, the campaign was a failure. It was a failure as we did not successfully push through the Turkish lines to Istanbul, and then on to attack the Germans on another front to help the Russians who were suffering heavy causualties at the time.
So, heres why we retreated: * Second thoughts in Parliament: worth the casualties??? * Supply lines were not working. Men did not get enough stuff * No one knew how to do an amphibious assault: we just rowed to shore * Lack of Leadership: General in charge changed, forces were not allowed to do anything without orders. When an order was given it would have to be carried out to the letter as it was from the British officers. No matter what. The orders were sometimes days old. * The Generals also had barely any knowledge of Turk tactics and the like. Their knowledge was very limited, consisting of things like a 1912 manual of Turk tactics, a tourist guidebook and an outdated map. * No additional troops allowed: parliamentay decision * Royal Navy withdraws: No pressure on Turk capital, army artillery support gone * Turks had the high ground (really high ground) * No one prepared for modern warfare: just ran against a machine gun, men shooting with bolt action rifles and pistols * Terrain very difficult * Naval mine-sweeps were poor. * A month's delay between the attacks in March and those in April...it gace the Turkish/Ottoman troops plenty of time to prepare and fortify. Kitchener depended on the element of surprise, but because of this he only gained "Tactical" surprise; when and where he would strike, not "if" he would strike.
Also, throw in the low morale of the troops due to the above factors, and also due to diseases such as dysentery and