There are two distinct types of Soldiers who serve: those who are here to make a difference (MAD) and those who are selfish and distracting (SAD).Each of us was equipped to be MAD, once we graduated basic combat training and our various military occupational specialty schools; we had the basic skills in our tool kits to be successful Soldiers.We all should have been ready to take on any challenge placed before us but this just isn't true for all of us.It doesn't take long to recall a Soldier who didn't even make it to their first duty station before displaying their selfish behavior, letting the rest of us know they are SAD Soldiers. Unfortunately, SAD Soldiers can be found at every duty station and at any stage of our Army careers.SAD Soldiers distract us from our daily Army mission. They distract us from taking care of the MAD Soldiers and their Families. They diminish our resources and steal our joy.As a staff sergeant with more than 10 years on active duty, I've sat through the same briefs a dozen different times, because of SAD Soldiers. I always tell junior MAD Soldiers if we are being told not to do something, it means somebody has already done it.Whether it is a small infraction, like being late to formation, or something much worse involving law enforcement, the SAD Soldiers cause the rest of us to stay late or hear the same thing for what seems like the hundredth time.What makes great Soldiers become SAD?For different reasons, they lost sight of the reason why they joined the Army. They lost that great sense of pride, belonging and accomplishment they had when they walked across the graduation stage. Their lapse in judgment caused them to forget they are Soldiers at all times and not just during duty hours.They lost sight of our Army Core Values: Loyalty, Duty Respect, Selfless Service, Honor, Integrity and Personal Courage. Yes, most of them can recite the core values without hesitation, but the importance of these values did not resonate enough for them to uphold Army standards.Time and time again, we look at leaders as the root cause of SAD Soldiers. However, just as each of us independently raised our hand as we recited our oath of enlistment, we must take personal responsibility for our own actions.Let's talk about what it means to be a MAD Soldier. You took an oath to protect and defend our American freedom and agreed to live by a set of military rules and standards.You are part of a great kinship that has stood the test of time from MAD Soldiers such as Lt. Col. Florence Blanchfield, the first woman in U.S. Army history to hold this permanent military rank, or Sgt. Audie Murphy for which an entire members-only club dedicated to leadership is named, or to Pvt. William "Willie" Johnston, who after begging to enlist with his father, was the youngest Medal of Honor recipient, who at the age of 11, assigned as a drummer boy to Delta Company, Third Vermont Volunteers Infantry of the Union Army, was the only Soldier to return from the Seven Day Battle and Peninsula Campaign with his drum.MAD Soldiers embody our core values and live by our Soldier's Creed. They have respect for authority, themselves and others at all times. MAD Soldiers fully embrace our higher standards 24/7 and 365 days a year.MAD Soldiers understand that being a team member is more than a cliché. MAD Soldiers do not accept the minimum. MAD Soldiers are always looking for ways to improve themselves, their Families, friendships, squads and local communities. MAD Soldiers choose to be MAD Soldiers at all times.So I ask you, "Are you MAD or SAD?"(Editor's note: This commentary is an adaptation from an article written by Air Force Master Sgt. Henry Strozier, 92nd Security Forces Squadron, Fairchild Air Force Base, Washington / Published May 29, 2015.)