One of the most persistent problems is that economic accords can have extraneous effects on another crowd are not interested in the contract.

For example, if the production of power has been done from coal, the pollution alters people all over the world like acid rain, global warming, etc. This is an appropriate problem as we cannot depend on the free market to arrange the most adequate conclusion. If the creation of negative externalities  are done by us then we won’t take them into our account and while making decisions how much to ingest. This is why we can get over-utilization of driving a vehicle into a city centre at top hour. If everyone enlarges their service, it doesn’t lead to the most adequate result – but bottleneck and wasted belongings.

Externalities, usually need some kind of authority interference.

For example,  negative externalities getting taxes (e.g. sugar tax) or diminishes on positive externalities (e.g. free public education) even banning vehicle in city.

But, even the explanation to market disappointment (e.g. taxes) which builds its own likely problems.