The Catholic Church has grown significantly over last century in numbers. She reportedly now has about 1.3 billion baptized members (presumably not all of them are active). In actual strength, however, she has not grown. It is something of an oddity to realize that the increase in people has not led to an increase in power. When we speak of an army, we would generally think that the larger the army the more strength it would have. That is not the case, however, when we are speaking about real strength (which is spiritual, not physical).
In things like humility, holiness, or wisdom, it is very difficult to believe that the Church has grown. I certainly do not know the mind of every baptized Catholic in the world, but Jesus did tell us (in various ways) that we "will know them by their fruits". This means that if the fruit of 1.3 billion Catholics is not good, then those numbers did not improve things. If the "fruits" of the Church today are coming to light as: pride ("who are you to tell me what to do?"), denial of sin (especially in the common refusal to go to confession even just once a year!), rejection of holiness (which is the same as compromise with the world), and a massive ignorance about what the Church teaches (which always results in large numbers of people making terribly foolish choices), then we can "know them by their fruits".
What makes this situation so hard to overcome is that these rotten fruits are seen not only in the laity, but also in the clergy. Many priests and bishops have fallen into horrible grave sin. Homilies, if doctrinally sound (which is not always the case), are often dry and lack any real encouragement for the faithful. Priests often give horrible advice to those who come seeking counsel. What will be the "fruits" of this rotten fruit? Sadly enough, it means that there will be many who will end up leaving the Church. Some out of frustration, and others merely because of confusion.
I mourn the fact that some souls will be lost, and others will be placed in terrible danger. Rather than anyone leave, I would pray that all would find a greater faith and return to what the Church has always taught (rejecting these modern innovations that come from the devil). I must admit, however, that that will not happen; some will be lost. Yet, those who remain will be largely those committed to a deeper faith and that means that the Church will end up growing stronger (even though she will also grow smaller).
Increase in numbers can mean an increase in faithfulness, but that is not always the case. When seminaries are not always orthodox, we cannot expect priests to teach the truth. When religious education for children is compromised in the parish, and often non-existent in the home, the children should not be expected to keep their faith. When RCIA prep classes are doing more to confuse the faith than to teach the faith, we should not be surprised if the Church's genuine strength has faded. How can we expect people to remain faithful if they were never taught how?
It is absolutely necessary that we work on strengthening the Church. That strength may come through greater numbers of children born to Catholic families, and through a greater number of converts, but not necessarily if those children and converts are not themselves strong in the faith. Let us continue to work on those things, but let us do it in connection with a good and effective plan of holiness, humility, and wisdom. Let us work toward the strength that endures, and thereby glorify our Lord.