I agreed with you on the part where choices do affect the nature of humans. Tom was indeed born normal, or rather neutral, and what led to his downfall was most likely the happenings he experienced. He never gotten a sheer bit of true love or enjoyed true friendship. He only gained a number of supporters because they feared or admired him, not love. He was never 'specially looked after' by Dumbledore, unlike Harry, never received or understand what is love, and only know what is hate and cruelty.

Yiting//Hufflepuff