You'd be surprised. There is a lot of poor quality on the market especially at the lower end. What amperage was you welding at? Which gas mix? The torch has a duty cycle and when you weld with gases with a her percentage of Argon, A light mix for example then this further reduces the duty cycle. Your videos are too short for proper anylisis but certainly looks like a wire feed issue to me and one of the most common causes is something to do with the torch.