It is the action labor takes when it fights in the direct, natural way and that which brings greatest results. When workers rebel on the job and slow down or cease work until their grievances are redressed--that is direct action. When workers, united as a class, conduct a general strike to defend their interests--that is direct action.
Workers are continually betrayed when they rely on other means than direct action--electing politicians to office, submitting demands to arbitration, or permitting the courts or government agencies to settle issues. These are methods designed to benefit the employing class.
To expect justice from these sources is as naive as to believe slot machines are made for the enrichment of those who put money into them. The only purpose of the infrequent payoffs is to maintain the faith of the gullible in the "justice" of a rigged machine.
Employers are vitally concerned only when labor uses direct action to win its demands, for it is a method that is not easy or cheap to combat. Workers have invariably gained more by acting directly than could have been won by playing ring around the rosey with employer-controlled agencies.
Direct action tore the chains of open slavery from humanity. Over the centuries it has established individual rights and modified the life and death power of the master class. Used fully, used wisely and well, direct action can forever end hunger, injustice and the mastery of humans by other humans.