One reason you might say "yes" is that you worry about being asked again. Will the ask come again if you say "no"? A better question might be: “do you really want to do _____” anyway?
All in Work
How To Do Your Good Work, Better
Imagine you’re in the middle of a conversation. It’s going well. The person in front of you is opening up and it feels like they are starting to trust you. You say “tell me more” or “say more”. Suddenly, it feels like the air has been sucked out of the room.
What happened?
This Is The Most Effective Way to Deal With Challenging Clients
Challenging clients don't trust you.
It may not be not be personal. Your clients may not trust the system that you represent. (Because you do represent a system or institution, whether you like it or not.) It may be the "healthcare system", for example, that they distrust or any another large, powerful institution. Whatever it is, people act out in challenging ways because they don't feel safe in the "care" that their institution offers.
Behind The Scenes: How do I stand up to bullying in the workplace?
Unless it’s spoken out against or prevented in some way, bullying will happen...because there’s no real reason for the bully to stop. But there are some things you can do for prevention and intervention.