Go to almost any writers conference, seminar, class, discussion, critique, or retreat, and you'll likely hear someone--either a speaker or a fellow attendee--warn against the use of adverbs, adjectives, or gerunds.
Now, go to the bookstore, pick up almost any book, and what will you find? Adverbs, adjectives, and gerunds.
Much like the pirate code in Pirates of the Caribbean: The Curse of the Black Pearl, literary rules are not so much laws as they are guidelines. There is a difference between what authors are told is acceptable versus what's actually published--did you catch that adverb?--so what's a writer to do? Are editors and agents just being paranoid or snobbish about this stuff?
Yes, and no.
We should be careful with what we put on the page, in the sense that we want our work to grab readers, to be fresh/original/inimitable (look! a list of three adjectives!), but words are there to be used, and there is a difference between "walked slowly" and "walked quickly", and sometimes ran, skipped, leaped, jogged, strode, ambled, strolled, meandered, or myriad other descriptors don't convey the actual moment the way we see it in our minds.
A great way to describe reluctance, for instance, is to tell us how a character acted; if he did so "slowly", then we have an obligation to say so.
On the other hand, as an advocate for non-lazy writing, I like to use strong, punchy verbs wherever possible. As a poet, however, I understand the importance of cadence, that sometimes sound and pacing are just as important as the idea itself, and can enhance that idea.
Like one gone mad I hugged the ground;
I raised my quivering arms on high;
I laughed and laughed into the sky,
Till at my throat a strangling sob
Caught fiercely, and a great heart-throb
Sent instant tears into my eyes;
O God, I cried, no dark disguise
Can e'er hereafter hide from me
Thy radiant identity!
Thou canst not move across the grass
But my quick eyes will see Thee pass,
Nor speak, however silently,
But my hushed voice will answer Thee.
I know the path that tells Thy way
Through the cool eve of every day;
God, I can push the grass apart
And lay my finger on Thy heart!
(excerpt from Renascence by Edna St. Vincent Millay, 1892-1950)
Renascence launched Millay's literary career, but one might argue that it is old fashioned and has no place in this discussion. After all, as the words in bold type can testify, it breaks the modern guideline of No Adverbs, No Adjectives, No Gerunds.
On the other hand, if a writer avoids over-using descriptors, his writing will gain punch. Or, in the words of Mark Twain, "You need not expect to get your book right the first time. Go to work and revamp or rewrite it. God only exhibits his thunder and lightning at intervals, and so they always command attention. These are God's adjectives. You thunder and lightning too much; the reader ceases to get under the bed, by and by." - Letter to Orion Clemens, 3/23/1878