Throughout history many individuals have believed they experienced an extraordinary private revelation in which God, the Blessed Mother, an angel or a saint appeared to them.
It is impossible to track all of the claims, as thousands of people every year believe they had such an experience. Some of these people publicly promote these experiences, while others never tell anyone besides their spiritual director.
The Church is clear that these private revelations are not part of the "deposit of faith" and are typically meant only for the individual receiving it:
Throughout the ages, there have been so-called "private" revelations, some of which have been recognized by the authority of the Church. They do not belong, however, to the deposit of faith. It is not their role to improve or complete Christ's definitive Revelation, but to help live more fully by it in a certain period of history. Guided by the Magisterium of the Church, the sensus fidelium knows how to discern and welcome in these revelations whatever constitutes an authentic call of Christ or his saints to the Church.
Private revelations gone wrong
Sometimes a private revelation doesn't remain private, and certain individuals will see in it an opportunity.
A recent document from the Vatican's Dicastery for the Doctrine of the Faith sought to address this issue:
[I]n some events of alleged supernatural origin, there are serious critical issues that are detrimental to the faithful; in these situations, the Church must respond with utmost pastoral solicitude. In particular, I am thinking of the use of such phenomena to gain “profit, power, fame, social recognition, or other personal interest” (II, Art. 15, 4°)—even possibly extending to the commission of gravely immoral acts (cf. II, Art.15, 5°) or the use of these phenomena “as a means of or pretext for exerting control over people or carrying out abuses” (II, Art. 16).
The person may have had a divinely inspired revelation, but then quickly succumbed to the temptations of the devil and used it for their own personal status.
Others may have never seen or heard anything, but knew that a private revelation could mean an elevated status and potential profit.
It is up to the local bishop to discern such situations and to impose limitations on those who use such experiences for their own gain:
If the alleged supernatural phenomena can be traced with certainty to a deliberate intent to bewilder and deceive others for ulterior motives (such as for profit or other personal interests), the Diocesan Bishop will apply, on a case-by-case basis, the relevant canonical penal norms in force.
What should be present in any private revelation are positive fruits of the Holy Spirit, which will help the bishop know that what happened can be traced back to God:
[Consider] the credibility and good reputation of the persons who claim to be recipients of supernatural events or to be directly involved in them, as well as the reputation of the witnesses who have been heard. In particular, one should consider the mental equilibrium, honesty and moral uprightness, sincerity, humility, and habitual docility toward ecclesiastical authority, willingness to cooperate with it, and promotion of a spirit of authentic ecclesial communion;
[Evaluate] the fruits of the Christian life, including a spirit of prayer, conversions, vocations to the priesthood and religious life, acts of charity, as well as sound devotion and abundant and constant spiritual fruits. The contribution of these fruits to the growth of ecclesial communion is to be evaluated.
Visions shouldn't ever be used for personal gain, and whenever the Church has recognized a private revelation, the visionary was often one who was persecuted and rarely gained any benefit.
