As I understand it, there are two types of achievements.
The first type of achievement is personal. I think this is the type of thing most people, myself included, strive for on a daily basis. These are things like getting perfect marks on exams, excelling physically, improving your body composition, getting a degree, etc. These things are methods of bettering ourselves as individuals. Most successful people in society proceed by excelling at personal achievements and going forwards from there. For instance, a medical student excels in his or her coursework and knows the proper physiology and anatomy of the human body well enough to become a practicing surgeon. For some, that in itself is a personal achievement.
The second type of achievement is more lasting. It isn’t a personal achievement, but, it is a sort of existential achievement. This requires broad vision and drive. I am having a hard time describing how it is different (but not opposite) from a personal achievement, so I will give examples. Establishing a library or a hospital or a school in a severely impoverished place in the world. Doing pro bono work with your advanced degree. Modifying a staple crop to make it more vitamin-rich, preventing blindness in millions of children. Bridging the gap of private and governmental space flight programs. This sort of achievement affects many, many people. It is the kind of achievement that can take the help of hundreds for the sake of one resounding goal.
While the two achievement types are different, they can have some overlap. Many (if not most) people spend their lives working for organizations with such broad oversight. I would include hospitals in the list of such organizations, and many doctors have larger goals to help as many people as possible. They provide a necessary service, but the pace at which they change the world is necessarily slow and personal. Often times, public health policies can have a larger impact on the face of a populace, but not always greater.
I guess the main difference is that personal achievements mean something to the achiever, whereas the other types mean something to others. I don’t want to make out pursuit of personal achievement as selfish; self-mastery is an important part of being an individual and life. Ideally, one can strive for both simultaneously and harmonize the two.
Personally, I am trying to accomplish both. I want to become a physician, which I think had feet in both territories. I want to participate in research that will come to fruition and affect medicine and quality of life globally. I want a stronger, leaner body. I am actively pursuing these goals; with time I will accomplish them.