Actually, that's only true of DC, because WB owns them. They can take as much time as they want to get it right. Course, that doesn't always work either. (See Superman Returns)

As far as Marvel goes, I don't think Avi Avid is picky enough. Fox treats the X-Men franchise as a red-headed stepchild. With the exception of Sam Raimi and Sony, Marvel's efforts of late have been less than spectacular.

BTW, you can add Iron Man to your list. Jon Favreau has left that project and it is currently without a director.