It's frustrating when a window breaks, but then at least the worst has happened. The glass has broken and then fallen to the ground, allowing you to clean up the mess and call a window glass replacement company. It can be somewhat unsettling when a window merely cracks. Is it going to break soon? Will it stay like this for years if you do nothing? When a window has cracked, the glass has lost its structural integrity, and this makes a break far more likely.