Small damage can spread quickly due to increased pressure on the windshield. Pressure can come from something as minor as going through a car wash, or changes in temperture. Chips that are less than a few inches wide are repairable. But, if a chip expands into a crack, you may have to get the entire windshield replaced. Which is much more costly than a simple repair. Keep in mind that small damage can spread quickly, reduce visibility, and lead to unsafe driving conditions. Its best to address small breaks before they become larger issues.