No longer can it be assumed that if we read the same book we will find the same story, or that we will even find the story that the author intended. We can decide what the character will do next. We decide who lives and who dies. Each contributes to the story to produce an ending sufficient for both. Granted, the author writes all possible endings and therefore has the most control, but it is the reader who picks which ending to take this time, which way the character will turn and to whom the character will talk.
Every navigational choice has to count.
All the options were created by the author, but have been put in a particular order of events by the reader. The author writes multiple stories and the reader chooses the path to take. Depending on the story and how deep the author imbeds links, this can create problems for the reader. It is all too easy to get lost in a hypertextual world. If the reader simply clicks on link after link it becomes very easy to lose track of the bread crumbs leading back to home.