For want of a nail

Yesterday, I told my friend that we usually miss out on small things when working on a bigger issue and that would ultimately lead to failure. It reminded me of a rhyme I had learnt in my formative years called "For Want of a Nail".  This rhyme is sometimes quoted to explain butterfly effect and chaos theory.

For want of a nail the shoe was lost.

For want of a shoe the horse was lost.

For want of a horse the rider was lost.

For want of a rider the battle was lost.

For want of a battle the kingdom was lost.

And all for the want of a horseshoe nail.