Earlier quoted context omitted.
Because Objective-C is far from being an horror language, but perhaps your impression (and so mine) is conditioned by your past experience with your languages of choice.
I'm probably being unfair, I've never actually done any development in Objective-C (I have in C++), so I'm going on how it "looks" from the code I've seen, I just find it very unreadable. But in fairness I haven't tried to get into it, and I'm probably biased toward the C#/Java style syntax...
The runtime method dispatch of Objective-C (protocols!) makes it possible. Basically Objective-C gives you what Qt had to kludge in with qmake/moc. And it's still pretty fast!
When I see how little code I have to write to do something basic in Cocoa/Obj-C, and how well it turns out, any problems I have with syntax go out with the window.