The last second on a timer does not actually last longer than the other seconds; it is just a perception due to anticipation. This phenomenon is commonly known as "time dilation" or "time perception."
When we are eagerly waiting for something to happen, such as the timer on a toaster oven ticking down to zero, our brain becomes more focused on the passing time. As a result, each second may seem to take longer because we are paying more attention to it. This feeling of time dragging on is a psychological effect, and it's not that the actual duration of the last second is longer than the others.
This perception of time dilation can occur in various situations where we are anxiously waiting for an event to happen or when we are engaged in a thrilling or suspenseful activity. It's a fascinating aspect of human perception and how our minds interpret the passage of time in different circumstances.