How much time do people waste in their lives by coming in early to work just to avoid being late in case something unexpected happens during the commute?

For example, your clock in time is 8:00 AM but you consistently arrive at 7:45 AM just in case there is an unexpected traffic jam from a car accident and your employer isn't lenient on circumstances beyond your control? You lose over an hour of your life every week and extending it out to everyone who has to do this, this is a lot of wasted potential.