Even if you’ve outlined your first draft, getting sidetracked is kind of allowed, because you’re exploring your characters, plot, and story in a different way. And if you didn’t change your outline accordingly, [the revision is] the chance to do that.
Kelsie Engen wrote the preceding quote in her guest post at A Writer’s Path, 7 Reasons Why You Should Outline Your Novel During Revision.
Reading it was serendipitous. When I reported my word count to my writers’ group, I commented that the outlined ending doesn’t seem to fit what I’m writing.
I got encouragement to finish my draft regardless of the outline, but I felt as if I’m letting the wheel go and allowing my ship to drift off course. But thinking that I revise my outline afterward makes me feel better about going with the flow and see where it lands.