My first issue of UNCANNY X-MEN was #155, in which the Dark Phoenix saga is mentioned only obliquely, and in such a way that made it sound fascinating. That drove me to go find the other issues.

I think it is also worth asking how many of comics’ most memorable stories were told in a single issue.

Not disputing the handiness of numbering. But I maintain that it’s put before content all too often, arguably to the point where comics might be better off without it, in terms of focusing on story.

And how much use is it on a long running series? Does issue #432 means you need to read #431? How about #430? Or #400? Or #151? Or #1? If you have to read a previous issue prior to the current one, then there’s a problem bigger than the numbering. But accessibility is another whole topic.

http://blog.comichron.com/2011/07/where-did-comics-numbering-come-from.html

No, I don’t believe comics should go the route of other magazine publishers — for the very same reason that we followed the sequential-numbering method of the dime novels and fiction magazines of the 19th Century. We want people to collect them all, and easily; and where you are in the serialized story is important. Story is more important, of course — but readers don’t like to work for their entertainment. It’s a simple thing to expect people to keep three Lord of the Rings movies in order without episode numbers; if you’re doing hundreds of stories in a multi-decade arc of continuity, every little bit helps.

That said, as my article notes, collectors WILL figure it out, regardless of how many title and numbering changes any given series has.

If it’s being done as a marketing stunt, though, the content really should step up to hook the reader. So many new number ones are just number two with a shiny cover.