Can coincidences influence an author’s work – and is there really such a thing as a coincidence?

Sometimes it can be hard to know how to start or to end a full-length novel. What makes most sense plot-wise? What would the reader like? What do writing rules say about an ideal prologue or epilogue? I have no idea. The last chapter of my novel Wild Hearted was a mystery till the very end. My biggest issue was whether to end the novel with the bad-ass gangster hero Tomor or the lovely heroine Luz. Which point of view would work best? Again, I had no clue. So what happened is I sat in my car, mulling this over, turned on the radio – a random channel – and… the Spanish artist Luz Casal was singing, the very woman who gave my heroine her name!!! I squeeled, ecstatic, because surely it wasn’t a coincidence. Luz would have the last word.