Answer:
I think Ben Franklin meant that if one makes excuses constantly, they would end up not doing anything because of how much they backed out. If you never do what you should, you won't be any good at it.
For the following questions,
If you do make excuses, you could write something like: Excuses hurt me academically because when I choose to back out on something, because then I am unable to learn or gain experience, etc.
If not something along the lines of:
I don't make excuses, then give the reasons.
Hope this helps