Issue resolution by team or SM

Hi,

This is the most confusing part for me…and not able to conclude anything
Scenario: Team is not able to meet the sprint goal in a sprint and one of the task is not getting completed, as one of the issue they are unable to resolve. Whether scrum master needs to pitch in here or need to wait and watch depending upon the stage of team development?
It is mentioned in Mike’s book that we need to wait and watch, if the team is already in the self
organized stage. We need to pitch in only only when the team is in different stages of team development(not yet self
organized). How we will know when the scrum master to pitch in and when we should leave to the team?

Any help will be apprecited.

I didn’t find the right solution from the Internet.

References:
http://forum.izenbridge.com/viewtopic.php?t=6892
P2P currency example

Thank you.