Gustave Flaubert, author of Madame Bovary, considered le mot juste as the key means to achieve quality in literary art. In a letter to George Sand he wrote that he spent his time "trying to write harmonious sentences, avoiding assonances." He sometimes spent a week in the completion of one page, never satisfied with what he had composed. He explained in his correspondence that correct prose did not flow out of him and that his style was achieved through work and revision. Flaubert published much less prolifically than was the norm for his time. His painstaking style of writing resulted in a much lower output over his lifetime than that of peers such as Balzac or Zola. He has famously been called the "martyr of style."
So, what do you aim for - Prolific output, or le mot juste?
To find out more about Flaubert, see Wikipedia