Accountability and honor go hand in hand.  

If a man is to be honorable, then he is to accept accountability.  That is, he is accountable for all that occurs in the accomplishment of some worthy goal.  If obstacles appear, and surely they must, he does not use them as an opportunity to excuse himself from accomplishment of the task, but finds a way to deliver on the end result.  This develops for the gentleman the reputation that he will see to it that anything he has promised to do will be done.  The obstacles are no excuse.  Overcoming them is the sport of the game.

But accountability has an important element that many men overlook or never see, that truly separates the men from the boys.

A man, and surely a gentleman, must be accountable to himself.  Blaming others for what happens to him in life is childish behavior.  It makes a man a victim of his circumstances, not their master.  A man does not blame the obstacles of life for his situation.  He makes conscious choices to manage his life around the obstacles so that he accomplishes what he sets out to accomplish.

If he has agreed to arrive at a particular place at a particular time, and he is delayed because the traffic is bad, it is not the fault of the traffic.  It is the accountable man's reaction to accept that he had failed to plan for bad traffic, and that his future planning will include that eventuality.  This is a simple example, but can be applied to many aspects of life.

Put quite simply, an accountable man, and a gentleman is an accountable man, looks at the obstacles of his life, and sees them as hurdles to jump, not barriers to progress.  When an obstacle appears, he seeks means to go over it, under it, around it, or through it.  He does not resign himself to being the victim of the obstacle.  Whatever he does, he does it as a choice.  He realizes that failing to recognize that he is making a choice is a choice in and of itself.  He must deal with his choices, and accept the consequences of his choices, whether intended or not.