One result is to make predictability even more difficult. The effect is, of course, not limited to the economy, but extends to networks of all kinds and to social interactions. This is one of the main reasons why we don't have effective explanations in ecology, epidemiology, or economics. The new area of complexity theory pays a lot of attention to just these areas, searching for a better approach. Despite intense study of AIDS, we cannot confidently predict the number of people who will be infected in twenty years' time.
Nobody knows how to predict stock-market crashes.
There are no big areas of reductionist causality in social science or management studies. When we find an explanation that seems convincing, it always turns out that for every expert there is an equal and opposite expert who can convince us of the reverse story. Nobel prizes have been awarded to economists whose theories flatly contradict each other. Therefore, it is usual that imposing linear expectations on the agents within a nonlinear system will backfire in the form of unintended consequences caused by those slippery interactions. Wishing to kill insects, we may put an end to the singing of birds.