Why is ESD important in the manufacture of circuit boards?

If you do not take ESD precautions when working on a circuit board, or when working with electronic components or assemblies, there is a chance that static charge on your hands or on other places could discharge through one of the components and damage it. Damaging a component means the circuit or assembly or component no longer works correctly, or even worse, will operate normally but will experience a reduced lifetime, ie, fail in the near future.