It’s true that not everyone can become a Pope. It takes a grand process of selecting the next one that will guide the Catholic followers. But it’s also true that only the Pope can decide which accounts they hear of are miracles and which do not qualify. During the end of his reign, a Vatican-appointed Miracle Commission looks through hundreds or even thousands of submitted miracles and decided which ones are confirmed cases of works of God. Theologists and scientists help with this process.
About 99.9 percent of these are medical miracles, meaning that they would not qualify in the Catholic faith as a miracle of God. A child with leukemia who has a 5% chance of survival would not count. He would have to have a 0% chance of winning for divine intervention to count towards a miracle that would be documented by the Vatican.
Most of the time, a Pope has to be involved in the miracle for it to count. If a Pope heals someone with his own hands or if a vision of Mary is seen, it is likely that the miracle will have a boosted chance of getting into the “book of miracles.” According to experts, “Miracles can be confirmed only if the healed person prayed solely to one person, such as John Paul II, during their ordeal. That way, there can be no mix-up when determining which person in heaven interceded on their behalf.”
Before the 1500s, even when a peasant would see Virgin Mary, a “miracle professed by the Vatican” wasn’t required to regard such a thing. But recently, with medical experts performing their miracles without prayer involved, the requirements are becoming quite steep, and therefore miracles are quite rare.