Several, in fact:
1. Tanga (German East Africa, November 1914)
A textbook example of how not to conduct an amphibious operation. Collect a mishmash of superannuated garrison troops and dump them into troopships without bothering with little details like acclimation or training. Sail off to place that no one in the entire force has laid eyes on before, while making no effort to conceal your intentions from the enemy, who consequently knows exactly where and when you are landing. Make absolutely no effort to obtain information on the area or any enemy forces or defenses beforehand, but just dump your troops on shore haphazardly, with no plan for what they are to do once they arrive there.
The result was that when the Germans opened fire on them the troops became disorganized, panic spread, and eventually the force commander, who never exercised any kind of control otherwise, ordered an evacuation, abandoning large amounts of equipment and supplies which went a long way toward keeping the Schutztruppe going for four more years. And eight thousand British and Indian troops were soundly beaten by one thousand German trained and officered Africans.
2. Kut (April 1915 - April 1916)
A completely lunatic idea; advance up the Tigris river from Basra to seize Baghdad. Even if successful you are several hundred miles from your source of supply and dependent on river traffic which can be interrupted by a single battery of artillery at any point on the river. And once you start your advance it will be perfectly obvious to any Turk exactly what you are trying for, so security will be impossible. In the event by the time the British force was halfway there the Turks had blocked the route with a large enough force to eventually compel its surrender. And forty three thousand British and allied troops were lost (thirty thousand killed or wounded, thirteen thousand taken prisoner) in a repeat of Saratoga.
3. The Somme (July 1916)
The actual preparation was kept secure, to be fair, but any attempt to conceal their intentions was negated by a week-long artillery bombardment, which even the dimmest of Germans would regard as a precursor to an attack. By the time the attack was launched the Germans were ready and waiting with ample reserves to hand to toss out any Allied troops who happened to get past their defenses. The result was entirely predictable.
