One example of this cautious and time-consuming approach can be seen in the aftermath of the appearance of the Blessed Virgin at Lourdes, France to Bernadette Soubrous in 1858. There were more than 150 alleged Marian apparitions in the five years following Mary's appearance at Lourdes in Europe alone. NONE of these were ever authenticated after subsequent investigation and analysis. The Catholic Church, to protect itself and its members, evaluates private revelations very carefully. Questionable - every alleged apparition event starts in this category.
Nothing is assumed to be occurring until a thorough evaluation takes place.
Fraudulent - a few alleged apparitions have been faked for monetary reasons or by individuals seeking publicity and attention. On other occassions, there has been an element of satanic involvement uncovered. The most notorious such case of this is Magdelaine of the Cross. Despite these phenomena, it turns out that on her death bed Madelaine confessed that she had given herself to Satan while still a young girl. Authentic - a select few private revelations are determined to be authentic in that they appear to involve supernatural intervention and act to strengthen the faith of those who follow them.