What are two most noticeable things about the neck of the tortoise?
1) Tortoise can move only when it sticks its neck out
2) It is also most vulnerable when it sticks its neck out. It probably takes 10 time more effort to harm a tortoise when it is in its shell than when it's neck is sticking out.
So, we need to stick our neck out to move ahead. This is to mean that we need to take some risks to make progress. Of course, it does expose us to risks and we may be vulnerable to attacks. But, unless we stick our neck and put a stake in the ground on issues, we will remain where we are. "Even if you are on the right track, you will be run over by the train if you do not move." The most common of all trains is something called 'TIME' which keeps running over us for every action taken or not taken.
Churchill had a nice saying about necking out. When he was making his case for uniting against Germany in world war two, French made fun of him that he would be jumping up and down like a chicken whose neck has been hacked off. Churchill said "time will tell who will neck and who will chicken." Churchill necked and became immortal for saving England.