Economy of words makes your message stronger. Using too many that are extraneous distract and dilute it. This is why adverbs, adjectives, and prepositional phrases often add extra bulk that should be trimmed. Being too wordy indicates lack of skill and trouble expressing what you want to say. When you’re talking aloud you can get away with fumbling around a bit, but not in print.
On the other hand, people who talk too much are usually annoying. Thus, by extension, it can be pretty grating when an author takes too long to say something. Readers are not the most patient people out there. Everyone these days is pretty busy and doesn’t want to waste their time with someone beating around the bush.
If you can say the same thing with less words, do so. Start by zapping adverbs by using a better verb, then see if those prepositional phrases really add anything to the story other than word count. Some writers have a tendency to add a prepositional phrase on the end of a sentence that is totally redundant. Make sure you’re not one of them.