Reading books by CIA folks over the years, Mossad has benefitted from Arabs that feel this violence isn’t reasonable, and provide intel to help stop raids. I can guess that Iran has helped with signal intel over time to determine who’s calling in tips, and left those people in place while cutting them out of the loop on this attack. Probably Mossad was getting false traffic from normal moles while all this was planned.

Sadly there’s not a good end for those informers post attack, they served their role to keep Mossad complacent, and likely died just after the strike.

All conjecture (I have no intel sources on this), but bad for Mossad if true. This would leave them back to square one on human intel if it happened.