They encourage conversation which is typically slow when a group gets together for the first time. They don't want to draw negative attention to themselves.
And, they really, really, really don't want to sound or look stupid or uninformed.
Once you use ice breakers to break the ice, the participant discussions flow comfortably.
They are an excellent opportunity to encourage more questions, exchanges, and sharing of experiences among participants.
These are sample ice breakers that you can use to start out your meetings, retreats, team building sessions, or training classes.