If you were called away during the electrophoresis procedure and were not able to monitor your electrophoresis run, what do you think would happen if the electricity were to remain running in your absence

During the process of gel electrophoresis, the DNA separates on the basis of charge to mass ration and forms bands as it moves towards the positive end of the gel.

If the electricity is kept running for too long, then the DNA will continue to run in the positive direction and might exit the far end of the gel. As a result, there will be no band formation due to which the experiment will become incorrect.