My main reason for believing in UR is that I have no confidence in myself. Now a Christian who believes the traditional doctrine may say, “well you aren’t supposed to have confidence in yourself; you are supposed to trust Christ!” But there is a big problem with this and I’m confident that its not just me. To assert that I must trust Christ to be saved puts the onus back on me to make sure I truly believe; even more, according to some soteriologies, I must have evidence in my life, good works, fruit, to prove that my faith is real, that its not a false faith that its not “spurious”. For a person like me this is a recipe for despair (and it has been). Only if I am confident that God never gives up, that he will use all his means available (and his means are infinite 
) can I rest in His grace. Its all about commitment; not my commitment to God, but His commitment to me.
A tree is known by its fruit; I’ve seen the fruit of the doctrine of eternal punishment in my life, in the lives of others and even in the culture I grew up in.