Dread can keep you from doing a lot of things. If no one is there to push you, to encourage you to do things, you might never do them. In life, you have a chance, but you don't always have enough courage to do them. Saying yes is very important to be able to do. If you say no first, you will never really know about what you said know to.
Sadly, sometimes i lack saying yes. My parents bug me about that ALL the time. They're right, and i've learned.