WsTrO

Does the law of equivalent trade apply to everything? Does it really means that you will get the amount of return upon what you out in? Lets take studying for example many says that if u study hard you will get good result. No doubt it is true. However other than study does the law of equivalent trade applys to other thing. I have seen and experience things that only hearts and souls are put in but the return was not even half of what was put in. Is it because that people are taking them for granted?