I am doing a paragraph on goals, referring to this quote:"those who attain any excellence commonly spend life in one pursuit ; for excellence isnot...

Another and
different interpretation of this quote is that once people attain
excellence in a pursuit, they remain focused in the same pusuit at which they
have experienced achievement. After all, the pursuit of excellence is an avocation in
itself.  The artist, the musician, the actor--all become absorbed in their excellence,
which they always feel can be improved upon, or taken to another aspect of excellence. 
Thus, the pursuit of excellence is not a static action; it is a continuity of striving
to better one's art or achievements. 

Although this pursuit
of excellence is a lifetime pursuit, it does not necessarily exclude all else, and the
price may not be too high, at all.  Consider those who are great--are they all unhappy? 
Certainly, they belong less to themselves than to their art or to their people if they
are leaders, yet their feeling of self-worth and accomplishment must be a tremendous
reward.