Things happen because they are likely, even with self-organization
When we observe that living beings (including humans and their economy) are self-organizing occurrences, i. e. their continued existence depends on regularly lowering entropy within themselves, this could be understood to mean that living beings were in some sort of permanent struggle against ever-increasing entropy. However, a newer theory, called Maximum Entropy Production, says that
Why do things happen?
Things happen because they are likely. In other words, things happen because entropy increases. Nothing happens only in systems that are at their maximum possible entropy already—we say they are in thermodynamic equilibrium. However, since the overall universe is still far from thermodynamic equilibrium, it is likely that any such system will eventually be subject