Some writers construct sentences that appear to be complete, having a subject and a verb, but the sentence doesn’t satisfy grammatical completeness or it simply confuses the reader. [EDIT]
One potential problem as writers grow more sophisticated is that as the sentences become more complex, the opportunities to create senseless or mangled sentences also increase.
Ultimately, writers should seek to be sophisticated but clear. A number of grammatical and stylistic issues can impair sentence completeness and clarity. Consider this on-line help: