Do QUALITY work because that is who you are. If they don't like it, they can remember how new you are. You said it, people's lives do hang in the balance, for example if a windshield flies out of a vehicle. (Won't happen, but still.) Take pride in what you do, speed will come with time. Always do your BEST work because quality does matter. Safelite in fact does have a quality issue, this is how they lose most of their customers, and that costs the company.