Everything thing is in our hands! Why do we often say that nothing is in our hands?

In the Indian society where I live, there are many Aunts and Uncles that say nothing is in our hands, meaning that God is handling everything.  I believe that our efforts can produce different outcomes, or karmas can produce different outcomes in life as well.  Everything is in our hands, we say the opposite often when someone in the community dies, but that’s given after a departed soul is gone than yes, in that case nothing is in our hands we have to let that soul move on.  Efforts during this physical life is up to each one of us.  So make each moment count, is what I try to do but its easy to feel lethargy and not wanting to do what we need to.  That is when I should remember that while I’m alive it’s in my hands and no second ever returns…I will continue to strive for this for my lifetime.