Factual error: Semi-automatic guns don't just click empty, like they do in a lot of movies. The slide would lock back until you manually cock the gun. Yet in the corridor of light scene, this is exactly what happens: Alice's gun just clicks when it's empty.
Factual error: Alice and Ada blow up a taxi by shooting the gas-tank. Shooting the gas tank of a car won't blow it up - as was tested by Mythbusters. (00:38:15)
Factual error: Rain injects herself with the Las Plagas parasite, which seems to take the form of a little scorpion. Little or not, it's not small enough to be pushed through an injection needle.
Factual error: Typhoon-class submarines have a crew of 163 men. It is impossible for Jill Valentine to operate a submarine on her own, even with help from Rain.
Chosen answer: Jill was unconscious at the time, while Claire was awake, therefore the loss of memory may differ by state of mind, or vary from person to person.