Rock got kicked up on the highway and put a mark with a thin horizontal crack in the windshield. I swear I could see the crack growing as I drove. I dropped off my kid an headed straight to the Safelite shops that closes in 30 mins. The crack still fits inside of a quarter, which is usually the size I hear determines if it can be fixed or not. I didn't want to wait a few days as the warm/cold cycles of this time of year will only strain the crack causing it to grow.
Guy takes a look at is and says that the pressure of the equipment he uses will likely cause the crack to grow when he attempts the repair. He promises me nothing has me pre-sign a "I know it might get broken when we try this" form. He does the surgery and it comes out fixed. No more crack. Plus they took AAA discount and the repair was like $83 instead of $140.
I'm pretty sure if I waited even just another day, that crack would have spread enough that the entire windshield would have had to be replaced. Oh, and did I mention (likely a few posts up) that I had the windshield recently tinted? That would have been about $150 down the drain.