It seems to me like Israel (Netanyahu) and the US (Trump administration) collaborated in this instance. Like a you rub my back, I'll rub yours. Clearly, Israel, US and Saudis would love nothing more than Iran to be gone... but then, when I saw Netanyahu talking up Israel's find, the jig just seemed to me way too obvious to be taken seriously.
For Netanyahu's part, a near-abandoned warehouse just waiting for tonnes of paper files (rather than say USB, digital copies or the like) to be stolen. It's kind of laughable in today's day and age. Which then gives some "wind" for Trump folding on the deal... it's just too nice a neat. The fact the Europe isn't towing the line of the US, and that China, Russia and all others who signed the agreement see it as a good thing that has been working, says to me that perhaps it was a good thing. And, I wasn't for participation in it when Obama signed on, and saw it as laughable -- but then maybe I was wrong in my skepticism.
Then as Ed alludes to,
IAEA have been carrying out surveillance and such would be difficult to hide. Not to mention, the risk of being discovered as deceitful by ALL who in good faith signed the agreement, Iran would have no allies. They really need Russia onside at least (like Syria did), but if they lied to Russia, China, not just Europe, US and rest- the risk of their own state going the way of Libya increases dramatically so. The end result even of all such wars, is possibly to be rid of Iran as the finale. So then, the security risk of Iran developing nuclear weapons deceitfully vs. just letting it go at least for the next decade or however long is required -- just don't seem worth it.