Because all the other Churches and religions to which I have been exposed, and there are many, while each has aspects of Christ’s Church and faith and holiness, each doesn’t have the whole package. In some, those aspects may be more appealing than the same in the Catholic Church, particularly if compared with a particular Catholic parish, e.g. the singing may be better [not only with choirs but everybody participates], the preaching more connectable [more down to earth, less dogmatic, even more understandable from an American instead of a foreigner], the pastor more charismatic [less an administrator and more a chum], even the congregation more welcoming [hospitality being a quality that is sorely lacking in many, particularly larger, parishes.] And that’s just the superficial items. How about the more democratic organization, the fewer and less constrictive “doctrines,” the more conventional stands on social and political issues, more open to personal thinking, interpretations, decisions…to tailoring beliefs to my individual needs and world view.
These aspects and their comparisons to the Catholic Church are real. The Catholic Church has many, many failings and foibles, particularly when viewed at the parish level. Nor does the hierarchical level come off well these days: sex and financial scandals, squabbling and factions. Ain’t easy to judge a Divine Church in terms of its human members.
To me, the difference is in the big one that divides Christianity from all other religions, You, Jesus, and in the big three that divides the Catholic Church from all other Christian Churches, Your Real Presence, Your Forgiveness and retention of sin, and Your Church, with Your Magisterium, Pope and bishops. While the Holy Spirit and I will explore each of these separately if that is His will in future meditations, I need to let You guide me to Yourself, Jesus, first.
All of us search for ultimate answers and many of us find it in the realm of the Spiritual. And this search unites us and takes on a collective form in a shared religion. God hard-wired me this way and then, in Your providence, revealed Your True Self over time, making a covenant with a family, a tribe, a nation, and the world through the Jews. That revelation increased in magnitude and depth until finally, knowing You had created us in His image and likeness, You finally appear in human history in that image and likeness in Jesus, the Divine Image, the Divine Expression, the Divine Word. Only in You, Jesus, do I see revealed the Truth, God, whom You showed us to be our Father, and the Spirit of their Love which You share. No other religion except Christianity can point to incarnational revelation, where You, God, actually became human and dwelt among us as a man. Since I can know through a myriad of witnesses that You walked, spoke, ate, drank, slept, and lived among us, then it is on that basis that I believe, I have faith, that You are the God-Man and what You told us in Your life and words are God’s life and words.
 “Men expect from the various religions answers to the unsolved riddles of the human condition, which today, even as in former times, deeply stir the hearts of men: What is man? What is the meaning, the aim of our life? What is moral good, what is sin? Whence suffering and what purpose does it serve? Which is the road to true happiness? What are death, judgment and retribution after death? What, finally, is that ultimate inexpressible mystery which encompasses our existence: whence do we come, and where are we going? From ancient times down to the present, there is found among various peoples a certain perception of that hidden power which hovers over the course of things and over the events of human history; at times some indeed have come to the recognition of a Supreme Being, or even of a Father. This perception and recognition penetrates their lives with a profound religious sense. Religions, however, that are bound up with an advanced culture have struggled to answer the same questions by means of more refined concepts and a more developed language.” Vatican II, Declaration On The Relation Of The Church To Non-Christian Religions, Nostra Aetate, Nos. 1-2.
 It pleased God to call men to share His life, not just singly, apart from any mutual bond, but rather to mold them into a people in which His sons, once scattered abroad might be gathered together (cf. John 11:52). This universal design of God for the salvation of the human race is carried out not only, as it were, secretly in the soul of a man, or by the attempts (even religious ones by which in diverse ways it seeks after God) if perchance it may contact Him or find Him, though He be not far from anyone of us (cf. Acts 17:27). For these attempts need to be enlightened and healed; even though, through the kindly workings of Divine Providence, they may sometimes serve as leading strings toward God, or as a preparation for the Gospel.(2) Now God, in order to establish peace or the communion of sinful human beings with Himself, as well as to fashion them into a fraternal community, did ordain to intervene in human history in a way both new and finally sending His Son, clothed in our flesh, in order that through Him He might snatch men from the power of darkness and Satan (cf. Col. 1:13; Acts 10:38) and reconcile the world to Himself in Him (cf. 2 Cor. 5:19).Vatican II, On The Mission Activity Of The Church, Ad Gentes, Nos. 2-3.