Some would say for the
good of
another or
others and a lack of
self-intetest.
I, however, don't quite agree. I think everyone does things that serve their self-interest in one way or another. It may be giving of material things to make the person feel better inside, spiritually. It is still of benefit to the person doing the giving or work.
You will not willingly do any act which causes only harm or unhappiness to yourself.