Edoardo Camili - Hozint's CEO - considers the Paris attacks as intelligence failures for 3 main reasons:
1. Failure in the detection and prioritization of threats;
2. Surveillance was inadequate and ineffective;
3. Member states failed to share information and coordinate their efforts.
More on Edoardo Camili's point of view on NATO review.
Krishnadev Calamur - senior editor at The Atlantic - describes Brussels attacks also as an intelligence failure with the fragmentation of the Belgian intelligence community.