One of the critical Aha! moments in a writer’s life is when s/he develops a distinctive writing voice and also fully recognizes that voice. Judging from my own experience, this is a process that comes in stages, not all at once. The distinctive voice may be there, but it may take time before the writer realizes it.
In reading a few emails written by my older brother, I noticed that his voice shines right through. I can hear him saying what he has written. (That’s a BIG clue in recognizing your writing voice. Another one is if you can’t stand to have someone else read your work aloud because they aren’t saying things the way you would.)
My brother doesn’t identify himself as a writer, although he is quite the speaker. He does announcing for various sporting events and he’s very good at it. My guess is (and he’ll correct me if I’m wrong) that he has never agonized over whether he has a distinctive writing voice. It has come naturally and without question precisely because he hasn’t thought to question it, whereas, when you embark on the path of a writer, all you can do, at least for a while, is question your voice (among many other things). I think this is because we writers are trying to pay close attention to our writing in order to keep improving upon it.
I also think that we have to break out of the pedantic writing we learned in school. We’re taught to try so hard at creating proper form that our writing becomes wooden. Unlearning that woodeness takes courage. (Is this flippa-flappin’ comma in the right place? Where do I put the adverbs again? Do I need to care about split infinitives?)
Courage is needed, and maybe some encouragement. I maintained a college-y style to my writing until my mother-in-law suggested I write as though I were painting a picture. The art metaphor worked and I loosened up. It took another several years before I recognized my voice, although others mentioned that they could tell my writing apart from that of other writers before I came to acknowledge my voice.
If you’re a writer and feel as though you can’t find your voice, break some writing rules, write as though you’re emailing a friend, and flick the writing teacher off your shoulder. Have someone else read your writing and see if they can hear you. Your voice is there.