I don't remember where I heard or read this, it has been too many years. This little diddle has been going through my head and hopefully jotting it down will release it from there!
For the want of a nail a shoe was lost.
For the want of a shoe a horse was lost.
For the want of a horse a soldier was lost.
for the want of a soldier a battle was lost.
For the want of a battle a war was lost,
And all for the want of a nail.
Just goes to show that even the little things count.