Don't get me wrong, I love story arcs. Well, some of them. But when a creator creates a character for an arc, the character is often at loose-ends afterwards.
Obviously, it's most overt with villains. Bane or Doomsday were created for one purpose. But are popular, so get re-used. The real problem for me, though, I think, is when new heroes are created for - or at least with - a certain story. They sometimes don't quite have the "reusability" of those created as an idea that were just cool heroes and had villains and stories made for them later. Because everything about their personalities is geared to that first story. Their supporting cast all fit in the right place for that story. But once that story is over, the subsequent villains don't click as well or the supporting cast is left with nothing to do or the hero doesn't have a reason to keep up the gig, as they've accomplished what was their one big goal. Worse yet is if the creator leaves after that story and someone new is left swinging in the wind with an entire cast designed and built around a single story that's already been told.
I feel like starting off with a major arc with new characters (not just comics, but other mediums) often means the first story is great, and then it goes downhill.
Still better than starting off with the idea of grand mytharc but no idea what it actually is, though.