Originally Posted by
baseball
A few good reasons to not take immediate credit
1. The good guys haven't figured it out yet. Why do their job for them?
2. Let's make sure all of our internal actors are safe and far away from scrutiny before taking any credit, thereby exposing our team-members.
3. They have other plans in the works with a similar or same profile. They do not want to compromise current operations by leaking what they did, and how they did it.
4. Operational security
That would apply if a nation-state were behind it. But terrorist groups want credit, notoriety, and publicity if for no other reason than they are competing with other groups for financial support from those willing to give it. Terror-minded folks with means tend to prefer to back winners who get things done.
For terrorists taking immediate credit is very important, such that their operations are typically planned to allow for that...to the extent that the credit-taking often has a built-in mechanism to validate authenticity. Example, send an encrypted announcement email to the media BEFORE the event, and then follow up afterwards with the key to decrypt. This ensures the right bad guy gets the media credit, but doesn't risk blowing the op with advance notice. Also if it fails, the reporter will never know what the email said (unless he sends it to the NSA for some reason).
Waiting dilutes the impact and allows other to falsely take credit.
The flip side of this is if the bad actor (usually state-sponsored) prefers to avoid scrutiny, they can arrange with other like-minded groups for multiple bad guys to claim credit simultaneously, thus confusing the issue. Fun and games with these guys.