Seems to me that we've done this before in another thread but, nay the less...
I vote for Halsey, but first let's give him his due. Halsey spearheaded what early response there was to Pearl Harbor: hit and run raids on the Gilbert and Marshall islands in February, 1942, and on Wake island in March; command of the "Doolittle Raid" (to many at the time, the "Doolittle-Halsey Raid") in April, then those tough naval battles off Guadalcanal in the fall. To an American public looking for heroes in a dark time, Halsey was the man. A fortuitous typo by a reporter even turned "Bill" Halsey into "Bull," and a legend was born.
Unquestionably a hero–at least that's how the U.S. public saw him. And yet, the very qualities that made him a hero also amounted to his undoing. Sure, war requires killing, but it also requires thought, a cold eye, and careful planning. Such qualities were not always high on Halsey's list of priorities. The battle of Leyte Gulf is the classic example, where he abandoned his post at the San Bernardino Strait to chase down a force of Japanese carriers deliberately dangled as a decoy. If it wasn't for those brave "tin can sailors" manning the escort carriers of "Taffy 3," the Japanese might well have smashed the U.S. invasion force off Leyte. That was bad enough of course, but even worse was his deliberate hesitation to admit error and return when summoned by Admiral Chester Nimitz, a result of a message that looked to Halsey like it was framed in insulting terms. Indeed, he didn't even RESPOND to the message for an hour, while Taffy 3 fought for its life. And then there was the great typhoon of December 1944, with Halsey ignoring the warnings and continuing operations in the face of worsening weather conditions. Three destroyers capsized and 790 U.S. sailors paid with their lives.
As to Kurita there were a number of factors that lead him to turn away. First, Japan was trying to win this battle, which meant that they needed a navy after the battle. If they lost the Philippines, they could no longer protect their supply line, if they keep the Philippines, they still needed a fleet to protect them again. Kurita didn't know the situation around him. He was heading to Leyte Gulf, and was changing formation from night submarine defense to day air defense when he ran into Taffy 3. He thought this was part of Halsey's 3rd fleet, so the carriers would be fast carriers. This was his major mistake.
He had 2 options. Continue to Leyte and risk air attack, or attack Taffy 3. His decision was to attack the carriers, but just to knock out the flight decks so he could continue to Leyte. Fast carriers are faster than much of his force. If he spent time organizing his fleet into a battle line, the carriers would be gone. So he ordered his forces to attack from where they were. He knew he and his 2 battleships would fall behind, but thought that his 2 battlecruisers and 6 heavy cruisers would damage the carriers quickly, and they could continue on to Leyte. This decision came back to haunt him when the battle did not end quickly.
The carriers were able to launch their aircraft, and now Kurita was fighting an air and surface engagement. This type of fight had never occurred before. For accurate surface gunfire, the ships must travel in a fairly steady course. To avoid air attack, they must turn wildly. The ships were not in protective groups, so they were falling prey to either the American aircraft or surface combatants. Kurita had lost 1 battleship and 4 heavy cruisers prior to this engagement. As the engagement went on, he lost 3 more heavy cruisers and 1 disabled. If he continued this fight, he would have nothing left afterward. He was down to 2 heavy cruisers. Being left behind, he had little idea on what was happening and why it was taking so long. His only recourse was to disengage and reorganize. Once he disengaged, his only options were to continue to Leyte or leave. If he went to Leyte, he would face the same fight again, against a superior (to Taffy 3) surface force, as well as air attack. He would be unlikely to survive. So he chose the only option left, he withdrew.