For example, if I were to apply to become a pizza delivery man, I'll find ways to simplify and optimize the traditional delivery process. Then when I open my own pizza store, I'll have the most efficient pizza delivery system, maybe this will be the killer service that will bring down Dominos and Pizza Hut.
So if you see a pizza delivery dude next time, maybe it'll be me... ;-)
For example, if you're actually considering the pizza delivery scheme, first research the maximal amount of efficiency that you would possibly be able to add to the system. Then decide if it is worth pursuing. This does not apply if you are passionate about delivering pizzas!
[1] Consider deliberate choice to be general advice for those with lots of time and the goal of doing something substantive. Or if you are young, newly graduated, and thinking about jumping into a startup with some friends.