This sentence probably has the following meaning:
(1) There is no need to care too much about the gains and losses of life, and it can't be stopped!
(2) People's fate is predestined, fate is predestined, and everything follows fate (I always disagree with this view, happiness is earned by myself, isn't it/).
(3) Everything should be relaxed and not forced? Some things (things) are not paid by us, and efforts will be rewarded! As long as we work hard, we have no regrets!