Night amphibious landings promise the ability to take the enemy by surprise, but this promise is often illusory. Meanwhile, night landings impose their own penalty in terms of confusion, poor navigation and a lack of cohesion. This answer will cover British doctrine, as well as Allied experiences in the Mediterranean. Other countries had different experiences. The Japanese carried out a lot of nighttime amphibious assaults in the Far East - their first landing on the Malay Peninsula took place just after midnight, for example - but I have fewer sources on their doctrine.

Amphibious doctrine in the British military largely developed as a response to the Gallipoli landings. These landings had been characterised by high casualties and major delays which prevented the landed troops exploiting their beachhead. The possibility of a surprise landing would avoid many of these issues; the landed troops would not have to fight, and could move rapidly to their objectives. A night landing would be one way of guaranteeing surprise, as the enemy could not see the troops coming. The 1919 Manual of Combined Operations laid down a standard procedure for an amphibious assault. An initial force would be landed at night to sieze the beach. Follow-on forces would be landed in safety once the sun had come up, to reinforce the first wave and to move to their objectives.

In the interwar period, this doctrine, based on initial reactions to the Gallipoli landings, was tested in a number of exercises. However, these were less conclusive on the benefits of night landings. A 1925 exercise held at Kasid Bay, India, found that the defenders could see the attackers a full fifteen minutes before they hit the beach. Heavy casualties would have ensued. Other exercises found that night landings resulted in confusion. Navigation was largely done by reference to landmarks ashore. However, at night, these could not be seen, meaning that the troops often came ashore scattered and disorganised. This was not a good thing for a successful landing. In 1934, an experiment was made with a dawn landing, which was hoped would be dark enough to keep the troops hidden, but still have enough light to navigate by. Instead, it proved to be the other way round; the landing force was spotted 3-800 yards offshore, while there was still considerable confusion. By 1938, the Manual of Combined Operations had moved towards daylight landings. Night landings were not absolutely ruled out (and were still practiced), but they were not standard practice. Instead, smoke would be used to hide troops on the approach, while the provision of tanks and naval gunfire support would compensate for the lack of surprise.

This doctrine was applied to most amphibious landings with a strong British contingent. The main exceptions came in the Mediterranean, where they worked with the US Army, which had less extensive amphibious experience and still emphasised night landings. Operation Torch, the Allied landing in French North Africa, was largely unopposed, with the demoralised Vichy French forces putting up only minor resistance. However, there were significant navigational difficulties, with frequent cases of troops landing in the wrong place. The American 168th Regimental Combat Team, landing on Beer White beach near Sidi Ferruch, became heavily scattered. Some elements landed on beaches 15 miles west of the planned beach. The landings in Charlie Sector, just east of Algiers, were delayed by up to two hours due to confusion. The 3rd Battalion, 60th Infantry Regiment, was landed on the wrong side of the Wadi Sebou river from the rest of the regiment, leaving it unsupported. Landing craft from the transport USS Leonard Wood plotted an incorrect course to shore, causing two-thirds of the craft to be lost to rocks and reefs offshore. General Truscott, commanding the 9th Infantry Division, summed the operation up well:

The combination of inexperienced landing craft crews, poor navigation, and desperate hurry from lateness of hour, finally turned the debarkation into a hit-or-miss affair that would have spelled disaster against a well-armed enemy intent upon resistance.

Operation Husky, the Allied invasion of Sicily, went off more smoothly. The landing craft crews had more experience with night landings, and there was more provision for navigation. Even so, there were a number of mistakes and delays. Elements of the Black Watch were landed 200 yards west of their planned beach, right in an Italian minefield, with eleven casualties resulting. Two landing craft carrying units of the 157th RCT collided in the dark, drowning 27 soldiers as they sank. The 180th RCT was scattered across several beaches. At Salerno, there were similar problems. On Uncle Green beach, part of the bombardment hit the wrong target; the landing craft, following it in, hit the wrong beach (Sugar Amber). The landing craft carrying the second wave for the Sugar Amber sector would also cause considerable delays when they landed on Sugar Green instead. Anzio was the final Mediterranean nighttime assault. Careful planning meant that there were few navigational mistakes, but there were still a number of collisions and other accidents.

The combination of experiences in the Mediterranean, combined with the thicker defences expected in France, meant that the Allies moved towards daylight attacks for Operation Overlord and Operation Dragoon, the landings in the north and south of France respectively. These assaults needed accurate navigation, as well as plenty of light to see by when clearing the thick obstacle belts. As such, a daylight assault was the only practical approach.