I dunno if that's always the case. I still love The Phantom Tollbooth.
On the other hand, I remember being really frustrated by a phrase from another book. (I think it was "Kneeknock Rise"? I remember exactly nothing else about this book, though, so it might not be that.) It was a description of a scene, and it said the dog was asleep, "arms and legs akimbo." Now, I was in... maybe third or fourth grade, so I had never encountered the word "akimbo" before, and asked my parents what it meant. They explained that "arms akimbo" was basically the only phrase in which it's used, and it means having your arms out to your sides with your elbows bent and your hands on your hips. But this just confused me further, because the book said "arms and legs akimbo." I had no idea what it was trying to describe, and could not picture it. I tried to draw a picture of what it seemed to be describing, and continued to find it baffling. My parents agreed that was odd, and suggested I talk to my teacher about it. The teacher was very dismissive, though, saying "well, obviously you've never had a dog, or you'd know exactly what they're talking about." Which...what? Why would you even say that to a curious kid? Couldn't you at least draw a doodle of what it looks like?
So yeah, being forced to stick with a book you don't like does leave a very strong negative impression.
I think the idea is that this particular drug isn't suitable as birth control, but having identified that this mechanism/biological pathway can work for birth control, they can look for a less toxic compound to achieve the same effect.