DC will not "handcuff their creators" to continuity.
Diane Nelson (DC Entertainment president) commented on the difference between Marvel's cinematic universe and their own: Unlike Marvel, DC will not require their writers and directors to work within a tightly woven framework of interconnected films. Asking their creators to "work with the same storyline or force them to hold back characters or introduce certain characters" wouldn't work with what they're trying to accomplish. "Ultimately, it hinders the ability for someone like [showrunner] Bruno Heller to come in and create Gotham.” (Via).
I don't think anyone would go as far to say that Marvel has made a mistake. After all, they're making millions of dollars and don't show any signs of slowing down. But lots of fans have voiced their concerns about the focus on connecting each film to the last (and the tv series, and the upcoming ones), stating that the stories are beginning to suffer. Could DC be on to something?