“There are two reasons adverbs and adjectives steal thunder from your manuscript. The first is a simple matter of swiftness. Excess words bog down sentences, making them sluggish. Crisp sentences, on the other hand, move nimbly, creating in the reader a feeling of lightness and ease.” -- I.J. Schecter in “Trimming the Deadweight in Your Manuscript,” published in the 2009 Novel & Short Story Writer’s Market, p. 46.This is the best explanation I’ve read for avoiding adjectives and adverbs. It’s why I find some stories tedious to read. The sentences are dense and plodding. Adjectives may be necessary in some cases, but using the correct ones, and keeping them to a minimum, is important.
I completed a short story yesterday and launched its journey in the submission pipeline. It's 329 words long, so there’s not a lot of fluff in it. Still, I made two changes. First, I replaced a verb with one that better described the action. Second, one sentence ended, “and saw his feral, green eyes widen.” In the scene, a husband is threatening his wife with physical abuse. At first, I changed feral to crazed, but realized neither was needed. The fact that the husband's fist is cocked and ready to strike and his eyes wide gives the reader enough information to figure out how his green eyes look.
This brings me to the second reason for avoiding adjectives and adverbs. The author calls it Taking the Reader for Granted syndrome. This happens when an author insults the reader by providing information the reader should be able to figure out given the situation.