Have you seen or read articles which discuss the problems with alter calls and the sinner's prayer? The problems which they cite state, in essence, that it causes a person to believe that it is in their own power to be saved by doing the things and saying the words that will bring about their salvation. As a consequence they believe they have become saved ....and perhaps they are---or perhaps they are not. The "magic" (because truly this is the same as magical thinking) isn't in the saying of words, or the coming forward when told to do so, or by raising of the hand, or what-have-you, to signify to the pastor in charge that you want and need Jesus. The grace of God comes on His terms at the time He chooses, not on our timetable or our terms. He saves us because we do not earn it in any way, not even our asking "earns" this for us. He saves us even while we were His enemies. How is that possible??? Because God is God. That answer may seem too simplistic, and perhaps it is. Have you ever said to your son or daughter "Because I'm your mommy (or daddy), that's why!". Sometimes nothing else needs to be said. End of story. God is good because He is...and He does what He does because He is good, not because we did something that caused Him to act. If anything at all, He put the desire in our heart, and then He drew us to Himself by supplying us with our desiring Him, because it all came from Him. But then why doesn't He do that for everyone? Because then it wouldn't be grace, it would instead be universalism, and universalism is unbiblical. God's grace extends to all, but not all are saved. It's simple, and yet it's complicated...and a sinner's prayer doesn't solve our sin problem, Jesus does.
There it is.
People put faith in a prayer, or in their faith, or in their works.... in ANYTHING BUT JESUS.
It is Jesus who saves, not ourselves with our wishing and praying. When He has mercy on us, He saves us by His power, not the power of our prayers. The power is of Christ not of ourselves. Too many are putting their faith in the wrong thing (self/works/formulas), but the Holy Spirit will come upon His own in power and reveal His glory, the glory to save even one such as I.