There is an economic law called the “law of diminishing returns”. At a certain point, if enough money is spent on a particular investment, the return is less than the money spent on it, so one has to look at other ways to allocate that funding.
Il existe un principe économique appelé « loi des rendements décroissants » selon lequel, à un certain point, les sommes investies finissent par dépasser les rendements obtenus, et il faut alors investir ailleurs.