SpongeBob SquarePants (Seasons 4-5, 9-Present)

SpongeBob SquarePants is an American animated television series created by the marine biologist and animator Stephen Hillenburg for Nickelodeon.

Why it's mixed

 * 1) People had mixed receptions on these seasons. Either people think that these seasons are good seasons or bad seasons.

Altogether

 * 1) Both of them has a fair share of good episodes such as "Fear Of A Krabby Patty", "Skill Crane", "Krusty Towers", "Friend Or Foe", "Roller Cowards", "Bulletin Board", "Mimic Madness", "Karens Virus" and more.
 * 2) The new HD opening sequence (albeit, in Season 9) is amazingly well done. Likewise, both of the art visuals and the animation (albeit, in Season 9 and the first half of Season 10) have gotten even better than before. It might make fans of SpongeBob cry for joy.

Season 9b-Present

 * 1) Awesome Animation that feels like a throwback to cartoons from the 40s and the 90s.
 * 2) It also has a really Great Choice of music.
 * 3) The characters have redeemed themselves from the dark ages (2008-2012)

Altogether

 * 1) Both of them has a fair share of bad episodes such as "All That Glitters", "The Thing", "Fungus Among Us", "SpongeHenge", "Squid Baby", "Little Yellow Book", "SpongeBob You're Fired", "The Fish Bowl", "Sportz?", "Ink Lemonade", "Spongebob's Bad Habit" and more.
 * 2) During production, the series was hit by massive budget cuts, forcing United Plankton to switch from traditional animation from Nickelodeon Studios and Rough Draft, to flash animation from Elliott Animation in Canada. That said, the flash animation itself (in the final thirteen episodes) looks horribly out of date and is a complete downgrade of the series, with constant framerate drops. As a result, the character designs look rigid, stilted, and ugly. Not helping is that this type of animation would later be used for Stephen's next and final series for Nickelodeon, The Simpsons Minis (2010-2011), and that show itself is no better.
 * 3) Almost all the characters have been flanderized beyond recognition and lack their original personalities:
 * 4) ** SpongeBob himself has gone from a funny sponge who just wanted his life to be better, into a malicious and bratty sponge who just cares about himself!
 * 5) ** Patrick went from a dumb pink sea star into a dumb "brain-sucking alien-like creature" that has a below-average IQ and is literally used as a plot device for the show.
 * 6) ** Krabs went from a lobster into a literal manchild and greedy psychopath who rarely acts his age and causes destruction everywhere he goes!
 * 7) ** Plankton went from a crazy plankton who wants the formula to himself into a carbon copy of SpongeBob, Patrick and Krabs combined and he also wants the Krabbie Patties for himself.
 * 8) ** Karen went from a weird-looking robot computer wife into a rude plot device in some episodes, though he is still likable.
 * 9) This season's new theme song is horrible and only sung by two people instead of a full chorus. All of the other music in this season is mediocre at best. Worse, the intro is lazily edited, using clips of several episodes within this season, as well as some from Season 9's intro; a couple of clips from said intro are used in the wrong context. SpongeBob's whistle sound effect at the end is even mistimed, as he did it too early.

Season 4-5, 9a

 * 1) It was the same era (Post-Movie to be exact) where it had a TV movie named "Atlantis SquarePantis" which is not well-received by viewers.
 * 2) While nowhere near as noticeable as Seasons 6-8, the flanderization of the characters was slowly starting to kick in depending of the episode.

Season 9b-Present

 * 1) It has weaker writing compared to the first three seasons and even season four of the show.
 * 2) The voice of the characters can act noisy and scream at their voice records at several times.
 * 3) The final episode in production order, "There Will Be Grease!", ended the show on a sour note. The last one to be aired, "The Goofy Goober Games", is no better.