Remembering the fallen was the idea but has gradually merged into a mythic heroic legend. Sadly, many fell due to command incompetence but this is hidden from popular view.
The navy got its sea-current navigation wrong and went to the wrong spot at Gallipoli, exactly under a cliff below the Turkish encampment. It could have turned and landed at the better beach-head but fired a salvo to let the Turks know the surprise landing was on and went ahead anyway. The men were fallen.

After defending Tobruk even after Nazi tanks over-ran them and then holding on, the troops went to Singapore. The commanders had no defence plan except to salute the Jap officers correctly. Men were fallen on the Burma railway. (The navy sent out two battleships with no air or sea escorts. Both were sunk). But we forget.