Why states gamble on short wars they cannot sustain

Why do countries start wars that must end quickly because they cannot survive a war of attrition?

Because they see war as the only solution to problems that also deny them the capacity for a long conflict.

The viewer points to Germany and Japan as states that repeatedly needed quick victories because they lacked the resources for long wars. The same strategic problems can create both the perceived need to fight and the inability to sustain the fight. Leaders come to regard war as the only available answer while their economic or material position rules out a prolonged contest. The result is a gamble on speed whose failure exposes the weakness that prompted it.