On February 11, 2013, in a particular exorcism conducted by the greatest exorcist of all time (excepting Jesus of course), Fr. Gabriele Amorth (then, before his death, chief exorcist of the Diocese of Rome), he commanded the devil to tell the truth on some matters. When an exorcist does this, the devil has no choice but to speak the truth, for he fears God and Mary. Here are the (translated) words of the devil regarding the inestimable gift of authentic private revelations to the Church: "[...] That one up there [Mary] is sad because every day She sees many of Her children falling to hell, despite Her continuous appearances, which hardly anyone believes. [...]" (Source: Mystic Post)
Through private revelations, Our Lady and Our Lord have pulled out all the stops to reach out to us before it is too late; thus, the demons have waged a constant and prolonged battle against private revelation via the hierarchy, seminary and other professors, pundits, errant Catholic apologists, the media, social media, etc. Their goal is to try to discredit authentic private revelations (approved or not yet approved) and to expose inauthentic "private revelation" to scandalize people into unbelief in private revelation as a whole. There is also the omnipresent question: "Has it been approved?" The Church has NEVER taught that private revelation has to be approved to follow it; this doctrine of the devil is another terrible error on the part of the faithful, who "pontificate their opinion" in this way. This is why Our Lady is sad. She and God have done and are doing all they can to reach out to us through private revelation, but mankind refuses to believe. The Era of Mercy in which we are living is about to end to be replaced by an Era of Justice when God says "enough." They have not failed us, but we have failed Them in being cautious to an extreme and not open. As St. Paul teaches: “Do not quench the Spirit, do not despise prophesying, but test everything; hold fast what is good” (1 Thessalonians 5:19-21).