Thomas the Tank Engine (Sharon Miller era and All Engines Go!)

"No Diesel, I'm sure The Fat Controller/Sir Topham Hatt means a really useful steamie! You'll never be that!"

- Thomas the Tank Engine, "Misty Island Rescue"

Thomas the Tank Engine is a anthropomorphised fictional tank locomotive in the British Railway Series books by Wilbert Awdry and his son, Christopher, published from 1945. He became the most popular and famous character in the series, and is the titular main protagonist in the accompanying television adaptation series Thomas & Friends. He's a little blue engine who works on the North Western Railway. He originally worked as the station pilot at the Big Station but longed to leave his yard to go out and see the world. After helping to rescue James from a nasty accident, Thomas was rewarded with two new coaches, Annie and Clarabel, and was given the responsibility of running the Ffarquhar Branch Line, where he works to this day.

Unfortunately, he was flanderized in the Sharon Miller era (seasons 12-16) of the original show and Mattel's reboot of the show All Engines Go!. During seasons 13-16, he was voiced by Ben Small and Aaron Barashi in the UK and Martin Sherman and Meesha Contreras in the US, respectively.

Why He Caused a Whole Lot of Confusion and Delay
NOTE: This will only focus on how he was butchered badly in the Sharon Miller era and in Thomas & Friends: All Engines Go!.

Sharon Miller era (seasons 12-16)

 * 1) He has gotten flanderized and has lost all of the charm and likability he had in the first eight seasons, though it varies whether he is in character or not in seasons 9-11. He has gone from an optimistic, cheeky, fussy, smart, and playful engine to a complete idiot who is always simple minded, hardly pays any attention to anything, mostly never listens to what Sir Topham Hatt or what another engine says, makes way too many mistakes, screws everything up and comes off as a stuck-up smart aleck whom he thinks he knows everything.
 * 2) *However, after season 24, he has been flanderized again, but this time he is now portrayed as a child compared to his original personality traits in Thomas & Friends: All Engines Go!, which is a real shame because Mattel and Nelvana began picking up from where the writing at HiT Entertainment left off, turning the franchise into a franchise for small children.
 * 3) He makes a ton of stupid mistakes and decisions, which shows how bad his character has gotten.
 * 4) *In "Splish Splash Splosh", he gets too carried away about playing with muddy water to the extent he sprays James, Emily, and Charlie for no reason other than just him screwing around (though the latter deserves it). Therefore, his wheels would've rusted.
 * 5) *In "Misty Island Rescue", aside from being a know-it-all who he thinks he is in the right, he makes bad decisions despite saying he makes good ones, ignores the Logging Locos when they need oil to build up steam, does not care about the common sense he is given, and says a lot of awful rhymes.
 * 6) **He even tells Diesel that he's not useful because he's a diesel, which is not only rude but also caused the reason why this film happened in the first place (although Diesel had previously caused him and other engines a lot of trouble).
 * 7) *In "Saved You!" (the episode that started his flanderization), Thomas wants to make himself a "hero" after being given the opportunity to take a fireman that rescued Lady Hatt's cat from a tree to Maithwaite for his own medal ceremony, when yet he completely messes everything up and has wasted everyone's time for his own idiocy.
 * 8) *In "Wonky Whistle", where he is at his absolute worst, he causes havoc with a wonky whistle by leaving the Sodor Steamworks by nearly injuring (or killing) a workman who was trying to fit the whistle on him by his ladder, does nothing about the animals that are escaping out of his van due to his wonky whistle until the very last minute, and before leaving with the van at the station, he nearly grabbed a man's hand off the handle while he was trying to close the trailer van's door! Thomas can be impatient sometimes, but he is not this impatient!
 * 9) *In "Sodor Surprise Day", he was the one who caused Cranky to drop a crate of fireworks that Gordon was supposed to take to the castle! Of course, he didn't mean that to happen, but it was still irresponsible regardless!
 * 10) *In "Day of the Diesels", aside from giving Belle a racist, negative impression on diesels in general, he ignores Percy for no reason, even when Thomas himself is doing nothing. Not even him getting trapped at the Diesel works by Den and Dart is easy enough to make you sympathize with him because of how unlikable he is in this film and hasn't even learned anything in the events of the special at all. He doesn't apologize to Percy for unreasonably ignoring him, and he doesn't apologize to Belle or the diesels for his racist statement.
 * 11) **Before flanderization, he had his moments where he would be careless and would occasionally mess things up or get himself into trouble. But in these seasons, he does it on a regular basis.
 * 12) He is a stuck-up smart aleck who thinks he knows everything. "Misty Island Rescue" showcases this as he thinks he is in the right all the time.
 * 13) Like Son Goku in Dragon Ball Super, he is a spotlight hog in seasons 10, 11 and 13-16.
 * 14) He comes across as prejudicial against diesels. In Misty Island Rescue, he told Diesel he wasn't very useful because he was... well, a diesel. And he never gets called out for that. In Day of the Diesels, he gives Belle a highly negative impression on diesels by saying all of them are devious.
 * 15) Speaking of racism, he is a hypocrite.
 * 16) *His bias against diesels is completely hypocritical because he thinks diesels would never be useful, yet he has been good friends with Salty, Rusty, Paxton and Mavis, all of which are diesels.
 * 17) In some instances, he doesn’t get any comeuppance, making himself a Karma Houdini.

All Engines Go!

 * 1) For starters, his new design, while cute, can be shockingly horrible to the point where it shockingly actually makes Lion-O's design from ThunderCats Roar and any other character in that aforementioned show look decent by comparison.
 * 2) *The worst part of the redesign are his two whistle valves, which are now too far apart compared to the original series (which had them close together).
 * 3) *He also very surprisingly no longer has his unique triangular eyebrows anymore, which is a shame since they made his original appearance iconic.
 * 4) *Last but not least, his dome is way too bright in colour and is too close to his cab.
 * 5) *His prototype/beta design is surprisingly even worse, as it looks more like a crappy off-brand Wooden Railway toy than the original Thomas. See it for yourself. Thankfully it was changed due to how even the designers presumably thought it didn't resemble Thomas himself.
 * 6) *And in general, its redesign very surprisingly fails to capture the same charm as its original design.
 * 7) He has very odd-looking facial expressions that look extremely uncanny, unappealing and cringe-worthy.
 * 8) He is shown to be very egotistical most of the time - for example, in the episode "Rules of the Game", he makes the other engines do his obstacle course his way. In "The Super-Long Shortcut", he acts all-knowing when he is making a delivery with Gordon but instead gets them both lost. While Thomas in the original can be prone to being egotistical and big headed in some of the episodes he's in like in "Thomas, Percy and the Coal" and the film "The Great Discovery", he of course sometimes has a reason why he is egotistical. But here, his ego in the All Engines Go series makes him unlikable just because the plot needs to happen.
 * 9) His new voice is shockingly extremely annoying and high-pitched, due to the annoying voice performances from Aaron Barashi in the UK dub and Meesha Contreras in the US dub. While Meesha does try to sound lively as Thomas (since it could be because he presumably is a fan of Thomas and Friends), the same cannot apply to Aaron since it sounds like he's bored or just didn't want to voice Thomas at all.
 * 10) He has received even worse flanderization than the one he suffered from in the Sharon Miller era as he is written as a complete child and a huge baby who always misbehaves and acts like a complete moron to the point that he makes his Miller era counterpart look even better in comparison.
 * 11) *He is now been turned into an annoying engine that wants to have fun rather than working, and also a whiny engine that complains and is ungrateful.
 * 12) For some reason, he's surprisingly allergic to hay, which never happened in the original series at all.
 * 13) Nobody ever grounds or punishes him for his selfish actions, making him a karma houdini that gives Caillou a run for his money.
 * 14) He is also really surprisingly bland as his personality could easily be placed in other characters showing that his personality with a few exceptions is not really original.
 * 15) Similar to Dolly Dalmatian, Thomas is heavily overused to the point where he appears in every single episode, even when not the main character. Because of this, the other characters are either relegated to supporting roles or are absent altogether.
 * 16) He's also a complete spoiled brat in the episode "Letting Off Steam", he gets into a fight with Percy just because he laughed at him.

Sharon Miller

 * 1) He was a much better character in the first eleven seasons and massively redeemed himself during seasons 17-24, until his flanderization in All Engines Go!, where he is portrayed as a literal child.
 * 2) There are a handful of episodes where he is likable and even has his original personality, such as:
 * 3) *“James Works It Out”
 * 4) *“Best Friends”
 * 5) *"Slippy Sodor"
 * 6) *“The Biggest Present of All”
 * 7) *“Henry’s Good Deeds”
 * 8) *“Toby and the Whistling Woods”
 * 9) *“Fiery Flynn”
 * 10) *“Thomas and the Sounds of Sodor”
 * 11) *“Happy Birthday Sir!”
 * 12) *“The Christmas Tree Express”
 * 13) **He is also likable in Hero of the Rails and Blue Mountain Mystery (although he is a bit flanderized in the latter).
 * 14) He still cares about his friends and his branch line.
 * 15) Martin T. Sherman and Ben Small do fantastic jobs voicing him until season 19, where they were both replaced.
 * 16) Depending on your view, he was a decent character for the first half of season 12. It wasn’t until "Saved You!" where his flanderization officially began, although to some, his flanderization started back in "Thomas and the New Engine".
 * 17) Despite the downfall of his character, at least his first flanderization isn’t as bad as his second one.

All Engines Go!

 * 1) While his new design isn't as good as his original one, it still keeps many features that made the original Thomas recognizable (e.g. the blue paint, red stripes and the number "1") and is admittedly cute. Additionally, he still has his original 0-6-0 configuration (whereas engines like Gordon and Nia had their configurations changed).
 * 2) *Additionally, unlike most of the other engines in the show, Thomas still has the iconic whistle sound he has had since 1984. This is a nice touch since said whistle sound is instantly recognizable.
 * 3) *When comparing the prototype design with the finalized design, the latter is the better one of the two since it looks far more like the original Thomas.
 * 4) One of the few decent things about his design is the straight running board that he was given. You can tell that the reason why Wilbert Awdry wanted to fix Thomas' design in the Railway Series story "Thomas Comes to Breakfast", was because he wanted to give Thomas a straight running board in the book Branch Line Engines.
 * 5) Despite being heavily flanderized on this show, at least he still has his original cheeky and optimistic personality from the original series.
 * 6) He still cares about his friends, including his BFF Percy.
 * 7) He was a much better character outside of this reboot and the Sharon Miller era of the original show.