Writing sagas or series

I just read some great advice for writing a successful fantasy series and I thought I'd share it with you. The difference between a series and a saga is that the books in a series are stand alone. You can read them out of order or individually, but to really be successful, the author hopes to compel the reader through the entire series. Many authors count on the appeal of their characters to keep readers engaged, but JK Rowling used a better strategy. All of the Harry Potter books had two story arcs, the individual story arc for that book, like discovering the chamber of secrets, and the larger macro story arc that spanned the seven book series. JK Rowling's macro arc was defeating Voldemort. In every book, Harry Potter gains more clues and resources to defeat the dark enemy. This macro story arc draws readers through the entire series, racing to the final confrontation. Most series authors understand the need for compelling story questions for their individual books, but many neglect the greater story arc. The greater story arc is the real key to a super successful series. If you are writing a saga instead of a series, then by definition, the greater story arc spans across all the books. The secret to making a saga work, especially a long seven book saga like Silk & Steel, is embedding strong underlying themes. Strong themes keep the writer focused and on track, they buttress the central story arcs and compel the reader to the last page of the last book. I believe success is in the big picture, in using greater story arcs and powerful underlying themes. If you're courting success, consider the big picture when you write your sagas and series.