The truth is once saved always saved is true,if you allow the Spirit to lead you to do what is right,for without the Spirit you are none of Christ's saints.
But once saved always saved is false,if they hold unto the belief that a person can never fall away from start to finish,which even Paul said if he did not do what is right he would be a castaway.
Even Paul said it is possible for him to be a castaway,shipwreck his salvation,if he did not do what is right,among other examples in the Bible.
Which then leads to the doctrine of predestination,where it really stems from predestination,for to believe in the misinterpretation of predestination,would lead them to believe they cannot fall,which one wrong interpretation can cause a domino effect of misinterpretations of other scriptures and faulty beliefs made up by them.
We have seen many examples in our lifetime of people who claimed Christ as Lord,and then stopped believing,some even going to the occult,and some becoming an atheist,and some not believing in any type of religion at all.
So if these people claimed Christ as Lord,and then did not claim Christ as Lord,then how do the people that believe they are the elect know if they are the elect,and know if they were sincere enough when they did claim Christ as Lord to be the elect,and how do they know if they might fall away,and if they say,well those people were not sincere when they claimed Christ as Lord and that is why they ceased claiming Christ as Lord,then how did they claim Christ in the first place if they were not sincere about it,and how did they claim Christ as Lord if they are not the elect,especially when Jesus said nobody comes to the Father except the Father draws them,and nobody calls Jesus,Lord,except by the Holy Spirit.
It would seem by the interpretation that they give of predestination,which leads to once saved always saved,that only the elect could claim Jesus as Lord,but we have examples of people who claimed Christ as Lord and then ceased,some even dying still not claiming Christ as Lord after they ceased,and how did they claim Christ as Lord in the first place if they are not the elect.
It would seem like only the elect,since they were chosen beforehand,without their participation,would be able to claim Christ as Lord and no one else,but that is not the case,for many have claimed and then stopped claiming,and the Bible says many are called but few are chosen,so if the elect is chosen beforehand,without their participation,then why is God calling people to follow Him and a lot are not chosen,when if they are not the elect why would God call them in the first place if they were already not chosen from the foundation of the world.