When to use it
Use it when you genuinely need something quickly. A specific time and a reason tell people how urgent it really is and why. “ASAP” means different things to different people, and lots of exclamation points can read as panic.
Example
You: “I need this by 3 p.m. today for the client call.”
Analyst: “On it. I'll send it by 2:30.”
In an email or Slack message
In Slack: “Need the updated numbers by 3 p.m. today. The client call is at 3:30. Can you make that work?” Asking if it's doable is respectful and gets you a real answer.