There really wasn't much of a story to begin with. It was about a little kid who was having a bad day, some of that admittedly was through his own little boy first world problems, some of it legitimately was going against him. They turned it into something I'd call "Liar Liar with Bad Karma instead of Lies," especially since the kid
wish inflicts the bad day on everyone making Alxeander even more of a d-bag than in the original when he was just baby George Costanza. While I didn't like the movie before that reveal, the fact that it's all inflicted via Birthday wish makes it just reprehensible.
While I don't think the Grinch movie improved on the original story, the film worked by taking the mythology and expanding on it with alternate character interpretation. Not a great film, but I do like how the Grinch wanted to destroy Christmas because he felt the Whos were hypocritical, and frankly that's something we can all jive too. Not to mention it was already a half hour special, and that seems to be the source they were using. Said special padded the story out with Chuck Jones animation, though.
Cat in the Hat however... I doubt the producers knew there was a special. It's not fairly well known (mainly because it isn't rebroadcast every year). Angry Beavers sort of referenced it... that's about it. And I might as well go there... something tells me Universal
knew this was a terrible film and they made it because they had the license and they wanted to punish Mike Myers for not doing their awful Sprokets movie that thankfully never happened. I mean, there wasn't an SNL skit movie that was a success since Wayne's World, so naturally one based on a lesser known skit that was only relevant in the 80's would have been a massive hit.
So when Tim Allen backed down (who would later go on to Last Man Standing, so it MUST'VE been bad for him to have standards) Mike was still under contract and they forced him into that film, and then his career hit hard (though this wasn't the film to end his career).
But yeah... Kid's picture books don't have much story, and they invent one whole cloth. Cloudy with a Chance of Meatballs took the sweet grandfather tall tale and rationalized it as a well meaning scientist who wants his father to be proud of him that did everything. And while I don't hate the film now, I still don't care much for it. Like I said, they made Shrek once. And that was all luck. And even then, the original pass of the book added some stupid, cliched stuff that thankfully wasn't in the finished product. Shrek was to live with his parents and be a source of embarrassment because he didn't want to be an ogre... no thank you. The 90 minutes of antagonizing Michael Eisner was far more enjoyable.