When I was about seven or eight, I remember how happy I was when my mother came home from a shopping trip and brought me my own personal dictionary. (Computers didn’t exist then.) I enjoyed pondering the definitions and the etymology of new words. When I could afford one as an adult, I bought myself a mammoth Oxford English Dictionary—fully equipped with 22,000 words. It came with its own powerful magnifying glass. Much later when I discovered the Facebook game, Words With Friends, imagine my delight? If you can relate to this, you probably love writing, or you could be a lexicographer.
My fascination with words led me to start writing poetry—the first poem I remember penning was at age ten. I believe a good poem demands word precision. I made endless drafts of poems studying every single word. Using a weak word is a mistake like writing a check with a misplaced digit. What if I accidentally wrote one hundred dollars when I meant it to be one thousand? I could cash it, but it would be ineffective.
Poetry held my undivided attention until a few years ago when I caught what I call fictionitis, and I doubt it is curable. While words matter in fiction as well as poetry, an author often has more leeway with novels and short stories. That said, one word can make a big difference. Beware of common, bland adjectives. A simple example is describing a character as attractive instead of beautiful or handsome. Then go on to giving details about the color of eyes, hair, etc. Similarly, saying a dog is unfriendly is not as effective as using the word vicious. Using powerful verbs is probably more important. Instead of a character simply taking an object, have them grab, snatch, or wrench it from someone. The common verb running is not as descriptive as sprinting, dashing, jogging, racing.
With the easy access to an online thesaurus, a writer has little excuse for using lame words. To be fair, most often the problem while writing fiction is oversight. One can become caught up in delivering the story, but a story alone is not enough. Writers need to focus on making characters, places, and actions come alive, and that depends on precise word choices.