When Steve shoots at the monster attacking Claire, he fires his twin Lugers at the monster at a rapid speed. Yet, the moment the player controls him with the Lugers during the combat mode mini-game, Steve fires the Lugers at a slow and ineffective pace. Also, the monster he does shoot is severely affected by the bullets during the cut-scene, but during combat, the creature is able to move and even attack once hit by the Lugers.
When Steve saves Claire from the Bandersnatch, he fires over 30 bullets with his two Luger pistols without reloading. Lugers can only hold up to 8 bullets per clip. Steve shouldn't have been able to fire more than 16 rounds at most.
It doesn't snow in Antarctica, at least not very often.
The twin pistols Claire kills a zombie for early in the game are Calico M100P, but are not 9mm as the game says. In reality they're chambered in the .22LR cartridge.
Obviously the scene where Steve shoots the monster attacking Claire could not have happened as it did: Steve would have been injured by breaking head and shoulder first through a large pane of glass and he would not have been able to shoot the monster and hit it accurately without looking at it first without recovering from the fall.
Even though Ms. Redfield and Steve are Americans, the information about them is in metric.
The crossbow fires much faster than a crossbow could possibly fire.
After Claire and Steve discover that Alfred Ashford dresses up as his twin sister Alexia and pretends to be her, Claire states "So there never was an Alexia after all," despite having previously seen a home movie that features both Alfred and Alexia when they were children in the screening room, and on Alfred's computer in his office.
It's never really clear why Albert Wester freaks out and tosses aside Chris Redfield, the man he's determined to kill for revenge and has firmly in his grasp, when he hears Alexia laughing on the computer monitor. He obviously knows that Alexia is in Antarctica and not on Rockfort Island.
When Claire Redfield raids the Umbrella Facility in Paris, she dives into a basement to escape the attack helicopter only to find it's full of Umbrella security guards all ready and waiting for her. How did they know that she would head into the basement, she could have easily been shot to death by the helicopter or taken a different corridor to evade its gunfire.
When Albert Wesker meets Claire Redfield for the first time, he explains that he was the one who led the attack on Rockfort Island and is overjoyed about Claire still being alive as it guarantees that Chris Redfield will come to save her, allowing Wesker the opportunity to have his revenge and kill him. But what makes Wesker so sure that Chris Redfield will come to the island to rescue Claire. He doesn't know that Claire had sent a message to Leon to inform Chris about her whereabouts. For all he knows, she may not have had any means to send word of her location to Chris yet. This plot hole is not present in the Dreamcast version as Wesker never encounters Claire Redfield at any point in the story.
It's never explained why Wesker suddenly decides that he has further use for Claire Redfield and lets her go when a few seconds ago, he was adamant to kill her as a means to torment Chris.
When Alfred Ashford introduces himself to Claire Redfield, he mistakenly pronounces his name as "Alford Ashford".