It gets worse with longer series. Right now trying to get all of the Wild Card series. Digital, it runs (from various places) 1, 3, 4, 6, 16, 17. Out of 17 volumes (soon to be 18 since it's still going). And since each story arc runs 3 volumes...

Paper...I...I don't WANT paper! (sob...) Though thanks to Harry for reminding about ABEbooks, I may be able to get some of them there and have them fall into a scanner. It still hurts to debind a book but these aren't exactly great monuments of literature anyway. (Kind of a superhero version of "Tales of the Vulgar Unicorn".)

The annoying part is not to long ago the first 6 were available. One reason to not delay to much when you see a book you want (even if you won't be reading it immediately).