The "No Hello" problem is when people send just "Hi" or "Hello" in chat and then wait for you to respond before asking their actual question.

This wastes everyone's time because the person getting the message has to stop what they're doing to say "hi" back, then wait around while the other person slowly types out their real question.

Instead of being polite, you're actually being annoying and inefficient - just say "Hi! I have a question about X, can you help?" all in one message so the person can actually start thinking about your problem right away, even if they're busy or away from their computer.