Continuity errors are rampant in sitcom TV since writers often forget small jokes that they write or the actors ad-lib lines that are brilliantly funny. However, these errors mean that characters can often act in ways that contradict their established personalities, whether this is going against their morals or established traits, often in service of a joke.
The Office has many continuity errors, such as Andy not knowing how to pronounce "chlamydia" despite holding an STD awareness seminar in a previous season. These errors can be small, but bigger ones make characters difficult to root for, as there is little consistency in their personalities.
When Erin Kissed Pete
Some fans believe that Pete and Erin are an improved version of Jim and Pam, and the two couples certainly have their similarities. Jim kissed Pam at casino night, leading to Pam calling off her engagement to Roy. Erin kissed Pete after work, leading to Erin running back upstairs and breaking up with Andy.
However, Erin's decision to kiss Pete goes against her previous characterization. Erin refused to kiss Andy before he broke up with his girlfriend Jessica because honesty is important to Erin. In Erin's defense, Andy had abandoned her to go on a three-month boat trip, so perhaps their relationship was over in Erin's eyes way before Andy came home.
When Meredith Kissed Michael
Meredith is known as the most promiscuous character in The Office, often making sexual jokes, flashing the camera or other characters, and at one point being caught on film doing a walk of shame, which she happily admits. However, Meredith claims to have standards, condemning Michael when he tells everyone that he is cheating with Donna. Meredith tells the audience, "I ask everyone in the room, are you in a relationship," grimacing at Michael's bad conduct.
Despite her scruples, Meredith kisses Michael at his last Dundies, despite literally seeing him get engaged to Holly in one of the previous episodes. Meredith kisses him without his permission, and takes pride in it, celebrating with "I'm not gonna be a good mom tonight!"
When Oscar Slept With Angela's Husband
Oscar is known as "Actually" around the office for always wanting to be right and has had arguments in the series about morality and politics. One of his "principled stands" as Pam puts it is to condemn Dwight for sleeping with Angela while she is engaged to Andy, asking Dwight, "what is wrong with you, she is engaged."
However, Oscar seems to forget his morals and sleeps with Angela's husband, the state senator, in the later seasons of the show. Some fans believe that Oscar may have been a good candidate for manager after Michael left, which might have given Oscar a slightly better storyline than one about adultery and lies.
When Michael Fired Tony
The Stamford merger was a stressful time for Michael and the staff, especially Tony who was unable to put up with Michael's management style and embarrassed Michael in front of everyone by calling him out on his treatment of the staff. Michael refused to acknowledge Tony's demand to quit, firing Tony in front of everyone instead.
However, in previous seasons, Michael was a nervous wreck when firing people such as Devin, and stated to Ryan that "a good manager doesn't fire people, he hires people and inspires people." Michael was embarrassed by Tony and lashed out, but if he had stuck with his advice, he could have saved face and been seen as a compromising and caring boss.
When Dwight Insulted DeAngelo For Wearing A Seatbelt
Dwight is a prideful character and lashes out when he feels insulted, such as DeAngelo taking his job or Jim making fun of his hobbies. DeAngelo's promotion made Dwight lash out, snapping "why are you wearing a seatbelt, you're sat in the back," as Michael drives them both back to the office from the last Dundies.
However, Dwight had no right to say that specific insult to DeAngelo, as Dwight has worn a seatbelt in the back of a car before, for example, Dwight sat in the back of Jim's car on the way to a sales call and tried to put his seatbelt on before Jim slammed the brakes and Dwight's head hit the driver's seat.
When Michael Gave Jim Bad Advice
When Jim confesses his feelings about Pam on the booze cruise, Michael encourages Jim to go for it, stating "BFD, engaged ain't married." However, Michael later dates a married woman, Donna, going against his advice which implies that if the person were married, they would be off-limits.
In addition, Jan and Michael's relationship is tumultuous throughout The Office, but the one thing Michael asked Jan "specifically" not to do was cheat on him, which it is implied that she did with her assistant Hunter. Despite Jan's alleged - and unconfirmed in the show - infidelity, and their rocky relationship as a whole, Michael would not like it if someone stole Jan away from him, so his advice to Jim is a bit hypocritical.
When Pam Gets Married On A Boat
Pam's marriage to Roy didn't occur for many reasons, one of which was that Pam didn't want Captain Jack to marry them on the booze cruise without her parents there. This may have been just an excuse not to marry Roy, but Pam seemed happy that Roy had set a date and was even cuddling up to him after the announcement.
On their wedding day, Pam and Jim escape to a boat on Niagara Falls and have a gorgeous ceremony with the captain, again without Pam's parents there. Pam stated earlier in the episode that she was sick of all the people at her wedding, and wanted the day to be about her and Jim, but getting married on a boat without her parents seems to go against Pam's earlier characterization.
When Jim Refused To Dress Up
Jim hates dressing up for Halloween. This character trait has been established since the beginning of the show, but Jim does deviate from his own rule when it suits him. Jim didn't seem to mind dressing up as Dwight to mock him, or dressing up in a tuxedo to make fun of Dwight's black-tie rule for Michael's party.
However, he refuses to support his wife and dress as Popeye, even after Pam pleaded with him to do so since it would match her costume. Jim seems to think that as long as he is making fun of Dwight, it is alright to dress up, but Halloween is much too childish to participate in.
When Dwight Tried To Get Jim Fired
Despite the many times they worked together as a team, Jim and Dwight have a long-standing rivalry. In season 6, Dwight is furious that Jim gets promoted to co-manager ahead of him and attempts to get Jim fired from his position by implementing an employee of the month scheme.
However, Dunder Mifflin already has an employee of the month program, which Dwight should know since he won it "for 13 out of the last 12 months," winning twice in February in place of a pay raise. Jim, Dwight, and even David Wallace should know about the program, and David should have questioned it when he called Jim later that day.
When Michael Rode Oscar's Bike
Michael loves being the center of attention, so it is no surprise that when Oscar is commanding everyone's attention, Michael takes his bike and tries to ride it. Michael could have been pretending not to be able to ride it, calling out for everyone to cheer him on and help him out.
However, most of the office workers know that he can ride a bike, since Michael brought in a bike for the Christmas charity drive, even riding it into the office. Jim especially would know this, since he brought it up when Michael came in, and Andy might know since Michael gave the bike to one of the waitresses they brought back from Benihana.