Ask HN: What's your #1 pain point when asking for a raise?

I'm creating a "stress-free" guide to salary negotiation for software engineers, and I'd love to know what those in this community feel has been the biggest pain in the butt or burning question when it comes to getting a raise.

I'll reply with advice to your questions here as well (I've helped hundreds of SEs already, but want to do more research), thanks for taking the time to help me out!