Let us start with an oft-voiced criticism of Arthur C. Clarke's _Islands in the Sky_ (1952): It is not up to Clarke's usual standards. I am sure that a knowledgeable science fiction fan could readily rattle off half a dozen novels by Clarke that are much better pieces of writing. I won't bother to try.
But that being said, is the novel really all that bad? If we look at Isaac Asimov's Lucky Starr series (1952-58) or James Blish's _The Star Dwellers_ (1961) and _Welcome to Mars!_ (1967), we see some juvenile fiction that is fairly weak tea. It's not really _bad_, mind you. But it is just... routine. Clarke's novel is much better written, and it may be fairly counted as one of the best of the Winston line of books for young readers.
The novel invites comparison with another excellent Winston juvenile-- Jack Vance's _Vandals of the Void_ (1953). Vance's book is unabashed, colorful, melodramatic space opera. Clarke's book is the opposite-- a low-key, quiet, realistic treatment of day-to-day life on a space station. Clarke was faced with a problem in writing such a book. If you are going to be low-key and realistic, how are you going to make your story interesting to young readers? There is in fact nothing more boring than a thinly disguised science lecture.
Clarke's solution was to set up a series of events that _seem_ to be mysterious and melodramatic and then to playfully deflate them. Thus, there are moments when it seems as if you are reading about space pirates, aliens, and deadly atomic missles. But in fact, something else is going on instead. Yet the seemingly mundane explanation manages to be just as interesting as the melodramatic scenario; and step by step, it reveals a bit more about the nuts and bolts of life in a space habitat.
Clarke was faced with a problem. He worked out a solution to that problem. He wrote smart and he wrote well. Do you want to gripe because he didn't turn out a classic?