When you know you are going to be away from home all day and you fill a zip lock bag with a spare mod, batteries, a bottle of your favorite juice, and a mini screwdriver. Then, you stand there wondering what you might need that you didn't put into the bag. So then, you snip off a section of coil wire and some rayon and add that to the bag.
As you drive off, there's that strange feeling that you forgot something... Dang, it was the charger! When you finally get home that night you realize that you didn't even open that ziplock all day.