For want of a nail the show is lost, for what of a show the horse is lost, for want of a horse the rider is lost, is part of a famous quote. This quote was by Benjamin Franklin.

It basically means don't neglect even the most simple of things because if you do it can cause much larger problems.

Starting a sentence with "for" can be grammatically correct, especially in more formal or literary contexts. However, it is not commonly used in everyday spoken or written English. It can give a sentence a dramatic or poetic effect.

Some say that an Army marches on its stomach. Some say that your

most important tool in combat is your rifle or that wars are won by the

threat of the bayonet. All true, but trench foot and frostbite have had

a debilitating effect on troops since they began marching into combat.

Modern warfare may not be as dependent on boots on the ground as

it once was, but, the health of the troop's feet can be costly. They once

said something about "for want of the nail, the shoe was lost, for want

of the shoe the horse was lost, for want of the horse the battle was lost

and for want of the battle the war was lost". We don't use horses much

in today's warfare, but the concept is the same.

I presume you mean that theater in which he was apprehended after shooting President Kennedy. That was named the Texas Theatre. He was there in hopes of escaping the police and hiding out for a while. He made a big mistake by not buying a ticket, which resulted in a call to the police and his arrest. A ticket that would have cost about 25 cents would have allowed him to watch Aldo Ray in relative comfort while awaiting nightfall and a new escape plan. For an extra quarter he could have had an extra large popcorn with melted butter, a candy bar and a soda. "For want of a nail, the shoe was lost, for want of a shoe, the horse was lost, for want of a horse the battle was lost, ....."