I believe it was Madeline L’Engle who referred to the first words of a novel as “an opening door.” I’ve also heard those words called “the hook.“ Years ago I read the memoir of a man who (in the 1930s) was a contract writer of a popular book series, when a series numbered fifty volumes. Virtually all plots of the books were pre-formatted, but he still spent a huge amount of time on the opening page. “If I couldn’t hold them on the first page, I’d never hold them.” Then, there’s always “It was a dark and stormy night,” the opening words of Edward Bulwer-Lytton’s (1830) novel, Paul Clifford. 

One of my readers wrote to me, “I read your book, True Confessions of Charlotte Doyle.  It was boring at first, but by the second page it got good.” 

Whew!