Catching up with family and friends is always very pleasant, especially if it involves eating out. It is even more enjoyable for a writer if some of those present are reading or have finished one’s latest novel. But if someone says they have read the second in your trilogy, but could not find the third volume on Amazon, it is embarrassing to admit you haven’t finished writing it.

Often the reading experience is out of our hands.  A friend has finished your novel after at last finding her Kindle charger. It was lost during the process of moving; she thought that may have been why the middle part of the book seemed to move slowly.
Whether your readers have a real paper book or are dependent upon electricity, they bring their own experience to the novel, it is out of the author’s hands. Sadly we can’t expect every reader to take a week off work and live undisturbed in isolation, so they can give our novel the attention we think it deserves. Those who devour a book in a week and get ‘lost’ in it are the writer’s dream. In reality people drop their paperbacks in the bath, can’t read their Kindle on the bus to work because it makes them feel sick, or lose their book down the back of the sofa. They read at bedtime and fall asleep after one page, or they wake up in the middle of the night with raging toothache and read their Kindle to try and take their mind off the pain, so that your novel is forever associated with misery.

Outside factors may encroach; family dramas involving lots of form filling take over just as they reach chapter three of your novel.
Even if reading is proceeding well, each reader has memories and moods; they read your words through a prism of their own.
An author whose novel is turned into a film may see his book as others see it. We have all seen a film and thought it unlike the book. I saw a film after enjoying a well known novel and thought the film was rubbish, felt indignant on behalf of the author. I was later surprised to hear him talking on the radio about how pleased he was with the film adaptation.
Despite your readers’ experiences and the impossibility of seeing into their minds, if they say they loved your novel and were left stunned by the ending you know they’ve read it ‘properly’.