Writing is so much like life; sometimes hard and sometimes easy. Much like a novel, each chapter has its own degree of difficulty and challenges. However, the ones that prove the hardest to write are often the ones that really define the characters. Working a protagonist through their arc can be painful and full of rewrites. In the end, it is what makes the story the story.
Like most people, I would really like a life full of easy chapters but what a dull and boring life that would be. Yesterday it was nice to have one chapter that flowed. Today, not so much. That is what life is all about.