Gunnery Sergeant Foley says at the beginning to the women candidates not to expect special treatment. Yet, in the very next scene when Segar, a woman, is doing push-ups next to Zack and Sid, Foley lets her go after only three push-ups, whereas Zack and Sid had done fifty push-ups and had to start over after seeing Lynette and Paula.
Just before the officer candidates take the oath and graduate a recruit announces, "All officers present." The candidates' swords are up on their shoulders but in the next shot the swords are in their scabbards.
After Foley pulls Daniels out from the pool, his medal ribbons are missing their devices (little stars etc.). They are present before he jumps into the pool. It's unlikely they would have just fallen off.
When Gunny Seargent Foley has Zack Mayo doing push ups in the sand pit, it's noticeable that his forearm sleeves are already wet from getting into a prone position to chew the recruit out, before he actually does it.
The beginning of the movie is set in Seattle, Washington, but when Zack gets on his motorcycle to leave from his father's house, it is outside the Naval Base in Bremerton, Washington, on the other side of Puget Sound. Seattle does not have a Naval home port.
During the graduation ceremony the students are wearing the Service Dress White uniform and the reviewing officers are wearing Service Dress Blues. In reality they would be wearing all the same uniform one way or the other but never different as uniform season requirements are dictated by a senior officer (usually an admiral in control of the Naval region).
Zach rides his motorcycle onto the base and immediately reports for first formation. First military bases require vehicles to be assigned a decal before letting them on base. Zach would have had to stop at the front gate and get a decal. But he is not a service member at that time so he would not be able to get a decal.
Foley asks Zack where he got the tattoo, to which he responds, "Subic Base." He meant "Subic Bay." We had a naval station there, but among military and families, you would just say the city or location. Also, he would have gotten it in town (Olongapo), not on base.
Some people have objected when Gunnery Sergeant Foley referred to newly-commissioned Ensign Seegar as "sir." This goes back to the training scene where Foley was telling then officer candidate Seegar, whose role was to act out of shape for the wall climbing scene, "You can never give orders to men!" It was not fully accepted at the time to address a female officer by her gender, but by the uniform. It was not until following years that this was regarded as outdated and unfair. Eventually, female officers would be addressed by their gender. Before the gender acceptance of women officers having authority over men of lower rank, it was not uncommon to refer to a woman officer as "sir" because the rank itself is masculine. Also, some women think that using "ma'am" reinforces their femininity and undermines their authority, and prefer to be called by the honorific "sir."
Most navel officers do not become aviators as flying is only a small part of navel operations. Having Foley and the candidates constantly bring up wanting to fly jets would never happen. Some of the candidates would probably want to fly but it would hardly ever be mentioned at OCS.
Supposedly, the OCS candidate school shown here at Whidbey Island (they never had an OCS in reality) is the basic starting point to fly jets after completing training. They make it a point to show the jet next to the new candidates in their street clothes, yet, throughout the movie, not one jet is heard, not one runway is seen, not one trip to a jet hangar is made, let alone visible, and made even more suspicious when Dela Sera at TJ's tells Zach about Paula, "that's a flight instructor she's with." A flight training school without airplanes.
During the factory cafeteria scene where Paula is trying to reach Zack on the phone, a co-worker mentions to Lynette that it's 3:40 PM on a Friday and she's not bragging about their weekend plans. A moment later when Paula runs from the cafeteria to find Zack, the clock on the cafeteria wall reads 12:50PM. Also, many employees appear to be eating lunch.
The goof items below may give away important plot points.
During the graduation ceremony, when Gunnery Sergeant Foley reports to the officer and falls out the graduates, he does an about face and steps off with his right foot. This is incorrect, as you always start with the left foot when marching.
The class, upon receiving their commissions, approach Gunnery Sergeant Foley and present him with a silver dollar, in return for their first salute. When Ensign Seeger receives her salute, Sergeant Foley says "Congratulations Ensign Seeger, Sir". He should have said, "Congratulations Ensign Seeger, Ma'am."
When Zack and Paula go to the motel to find Sid they knock on the door with no answer. Zack goes to open the door with nothing in his hands. Cut to inside showing Zack and Paula going into the room through the door. Now Zack has a credit card and wallet in his hands indicating he probably jimmied the lock with the credit card to gain access.
After Sid DOR's (dropped on request) and Mayo confronts Foley, Mayo's complete disrespect towards his drill instructor and profanity at that point would have automatically got him booted from the OCS program.
Given the many witnesses at the blimp hangar, Gunnery Sergeant Foley would have been prosecuted and dishonorably discharged from the Marine Corp for fighting with an officer candidate, as it was a flagrant violation of the cardinal rule for instructors not to "physically assault, attack or cause bodily harm to any officer candidate or enlisted person" unless it was strictly for training purposes and even then only with medical services present.
After Sid DOR's and Zack goes to Paula's house, he tells her that he doesn't know where to look for him. Yet, he and Paula and Sid and Lynette had already been to the Tides Motel several times, so how could Zack not know where to begin looking for Sid?
Sid's suicide makes absolutely no sense. He tells Zack weeks before when they were having dinner with Sid's parents that his "girl back home" (Susan) was waiting to be married to him. So, after Lynette's rejection to Sid's marriage proposal, he didn't have to swallow the diamond ring and kill himself, he still had feelings for Susan, and all he had to do was go back home and marry her.