I used to ask this question of Christians. My first motive was to paint them into a corner that made their God - and by extension, them - look either wishy washy or harsh. My second motive was to justify my unbelief (given either position). My third motive was at the root of the first two, namely, I loved darkness and was a slave to sin.
When people now ask me this question, I tell them that whatever either of us think concering other people will be irrelevant when we stand before God. There will be no waffling on and on about this person or that person, some lost tribe in a remote jungle, a baby that died in the womb, a man who died at 80 but had the mind of a 2 year old. It will be me and Him, it will be you and Him. There will be no hiding behind anybody else's account of their life.
Which is, sometimes, a good opportunity to ensure that the person asking the question actually understands what the Gospel is.