These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: The Cosby Show
Alternative Character Interpretation: There are times when Clair can really be something between a control freak or outright tyrant. While it's most often Played for Laughs in her not allowing Cliff to do some things he wants and in other cases, but it really isn't appropriate for her to call ahead to a store where Cliff is a regular customer and telling the owner not to sell him anything; it hurts the guy's business and she has no right to make that kind of demand as it's not her property. The punchline of this every time it comes up is the fact that Clair is a lawyer and she'd find some way to get back at them.
One episode in season 3 supports this as we learn just who Rudy got her incredibly bossy attitude from.
Theo also brings this up in one episode when he flat out tells Cliff, "Your wife won't let you do anything." That degree of control may also be why Theo himself views marriage as the place where the romance goes to die.
Award Snub: Bill Cosby himself stated that Phylicia Rashad deserved an Emmy for her performance on the show numerous times, but was never even nominated.
In the "Lookback Special," Cosby again mentioned this, but then said (paraphrasing), "When you look at the kinds of things she'd be up against today, she doesn't need it."
Big Lipped Alligator Moment: Clair, what are you doing behind a giant teddy bear in the living room? Yes, it was used for Season 3's Hide Your Pregnancy but it had absolutely no connection with anything in the episode nor is it ever brought up again.
One episode in Season 6 has Clair going away for a weekend retreat due to stress. As she leaves, the girls chant "Go, Mom!" repeatedly. It's a moment that doesn't match up with parting scenes from previous episodes, contributes nothing to the greater plot, nor is anything like it done again for the rest of the series.
Crosses the Line Twice: So a taxi carrying a pregnant lady crashes into Dr. Huxtable's car and he has to deliver her baby right there. Despite the adrenaline rush of an emergency situation for the characters, it's made hilarious for the audience.
Hilarious in Hindsight: In season 6, Martin says he's excited about the prospect of seeing B.B. King perform live (but ends up not getting to). Later in the season, in-universe character Riley Jackson, played by B.B. King, performs for the family.
Several years after the show ended, Joseph C. Phillips, Martin's portrayer, was cast on General Hospital. Shortly into his tenure, BB King made a guest appearance on the show.
Humor Dissonance: "Theo's Gift," the episode where Theo finds out that he's dyslexic. While the episode finally did explain why Theo struggled so much in school, his diagnosis is mostly played for laughs.
Averted later on in future episodes with Theo using it as his motivation to excel rather than let it hold him back any longer and all of those moments are played seriously.
Jumping the Shark: The series really hit its stride in the second, third and most of the fourth season. It began to turn downhill a little bit in the fifth and sixth seasons, but was still on top of the game. The seventh season began on a high note, but then came Pam.
The ratings support this as well. The show was #1 on TV from Seasons 2-6. Between Pam and the sudden competition the show faced when Fox scheduled the second season of its new hit The Simpsons directly against it, Cosby slipped to #5 in Season 7. It fell to #18 in its eighth and final season.
Bill Cosby himself said this happened as early as the third season when, after Phylicia Rashad had her Hide Your Pregnancy time, Cliff and Clair's onscreen romance moments become much less frequent.
Pam Tucker. Heavily evidenced by the fact that her character isn't even mentioned in the "Lookback Special" released as part of the Season 1 DVD collection, and in the Complete Collection's special features she is only shown in a single photo, completely alone, in the gallery. People viewing it for the first time may not even know who it is.
Seinfeld Is Unfunny: The many, many imitators that have come since make even the best of Cosby episodes seem stale and dated.
Small Name, Big Ego: Cliff honestly believes that he is the most distinguished graduate to ever come out of Hillman College.
Vanessa has a moment when she thinks the tryouts for drum major were redone because people saw how good she was and protested.