1) A simple, ascii A-Za-z0-9_ identifier unique to program/service is not required to use my program/service.
1a) My program/service cares deeply about your real world name and all it's nuances and variations. It requires full and complete understanding of your name rather than just a simple authentication mechanism.
2) My program/service will correctly handle the worlds naming conventions past, present, and future to the exclusion of other features / actually shipping some day.
3) Instead of following 80/20 "rule", my program/service will names 100% perfect!
4) My program/service will cater to all languages/cultures/subcultures/niches past, present, and future rather than any sort of target audience.