When we were at the Teradata conference, one of the speakers quoted Sir Winston Churchill as saying:
"If you are going through Hell keep going"
Now I am sure that this is not one of his most prolific statements and from sports we have many more, but I like this one better than:
"When the going gets tough, the tough get going"
As a metaphor or simile (not sure which is appropriate here) the vision of when your life or project seems to be hellish (usually the beginning and the end), this is the time you need most to focusing on the objective and keeping on going.
At Project X Ltd we have some great people and I am always amazed and proud about how they handle adversity and challenge. Not to say that we do not stumble, but I love to watch as the team or an individual picks up, takes ownership and then just keeps driving through Hell.