What does this proverb mean?
For Want of a Nail 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 message was lost. For want of a message the battle was lost. For want of a battle the kingdom was lost. And all for the want of a horseshoe nail.
It means that very small problems, which you might feel do not need to be dealt with urgently, can have very serious consequences. So therefore, deal with problems when they are still small and manageable.