Final answer:
After an electrical shock, movement is discouraged due to the risk of ventricular fibrillation and potential muscle or nerve damage, which necessitates immediate medical assessment.
Step-by-step explanation:
The primary reason why a person should not move about after receiving an electrical shock is that the heart may experience irregular and ineffective beating, known as ventricular fibrillation, which can be fatal due to a lack of blood circulation. This dangerous heart disruption often persists after the shock, making immediate rest and medical attention crucial. Electrical shocks can also cause muscle and nerve damage as well as burns, depending on the current's intensity and concentration.