Except I havent actually broken my phone. My point with that statement was that the monetary loss is more or less irrelevant to me. To me, the overall worse feel is not worth the potential savings. Honestly, if the phone broke so often that I had to replace it every month, I'd switch to another brand.
And your assertion that the phone will break is a logical fallacy. Chance has no memory. I could hypothetically drop my phone 1,000,000 times and not shatter either side. Someone else could drop theirs just once and have it shatter into a million pieces. A case doesnt eliminate that possibility either. Just reduces the chance. By your logic, even with a case the phone *will* shatter; just later. So why bother? You'd have to spend the replacement cost either way, right?
There's a quote by Dr. Cox (from scrubs) that I always keep in mind: "statistics break down at the individual level" - statistics only give you information about a population; they tell you nothing of what will happen to one person. At the individual level, there are too many variables to be able to give a real probability. Someone who's extremely careful and generally protective of his gadgets may only break the phone 1 time in a decade. Someone else may break on average 90 per decade. In the population, the failure rates averages out to the population's probability of breaking the device in a given time period... But you cannot make an assumption about an individual without taking all the confounding variables out of the equation.
You'd switch to another brand because YOU didn't protect it properly? That's ridiculous.
I know it's not 100%. You do what you reasonably can, and that's put a decent case on it. I have an Incipio dual-layer case that drastically reduces the energy imparted on the corners when it drops. Yes, a drop could be so bad that it still shatters, but at least the vast majority of the time, it's a non-issue. Over it's lifetime, even in a case like that (much less an Otterbox), it's not likely to shatter. Without one, it's vritually guaranteed to shatter. That's why almost all iPhones have cases on them, and of the few that don't most of them have cracked or shattered screens.
Yes, there is individual variation, that doesn't excuse you from taking what precautions are reasonably and easily available.