What happens is that when an idea that goes contrary to a what a person believes they tend to get riled up, and justify their stance in all kinds of ways.
People who are believers, from the heart, and seek out Yahavah and they desire to go by his ways, that is great. That doesn't mean that person can never fall into a bit of doubt, or even consider other things rather than the things of Yahavah in turn being choked out by other things and ways which are not of the LORD. Those who are indebted and desire to continue their relationship with Yahavah, could say I am saved, and I ll never doubt the promises of God, and therefore I am saved forever. While in theory that predication seems logical, it's also deceiving in the fact, that you have to make the choice every single day to bring God into ones life... while today is today, do not harden your hearts...
Some people can become hardened, even if they are faithful and they can depart and turn from the living God, with an unbelieving heart. Why do people desire to ignore some scriptures, for some vain traditionally taught pseudo claim "You can never lose your relationship with Yahavah," You can terminate that relationship by your own choice, and YAhavah will be a God of love and allow you to go that way. That is why there are warnings against falling away, and not become unbeliving.
While some may believe and never become unbelieving again - that doesn't mean other people are not subject to not becoming unbelieving again just because you do not see yourself losing faith, endure to the end and you will be saved... right? That is not once saved always saved, that is just believing and being saved to the kingdom, in hopes of getting to be with Yahavah one day. It's an on going choice daily, to choose and bring YAhavah into ones life.
To be like well I am never going to lose faith, and I m telling you I am saved and always saved - is a bunch VAIN BS... and inconsiderate of others and what they are trying to share and show. That is not love... in fact that is self preservation, to some degree selfish.
I have willing contemplated in my own mind, distancing myself from YAhavah and the Son of God, over a three minute period of thought, but perhaps my experience is not real, or perhaps I was never a Christian just because I had the thought some may say.
Overall when it comes down to the subject title, once saved always saved, people being lied to in and through churches and maligned by churches that have, excuse my language "f" them over, is sad, cause some people do end up leaving the faith, and not every church you go to is accurate with truth some hide the truth away in order to just make you "feel" good. It's not true. It's a daily choice to put Yahavah in your life, from your heart, and he sees that and knows that, and those who do not desire him, he sees that and knows that and continues to call out to them even so.