I suggest that the difference between yourself and x0x0 is mostly personal, not a difference in phones.
My wife is hard on her stuff; even with a case, her phones (one iPhone, two Android) need replacing every few years.
I don't use a case, and except for slightly lower battery life, my Android phones still look brand-new 4 years later.
I used to destroy phones fairly quickly until I stopped keeping my wallet and keys in the same pocket as my phone.
I treat my smartphones like garbage and have only ever broken my iPhone 6 (shattered screen). I still have all of my Android phones since the original T-Mobile G1 and they all still work.
Now that Nexus has the fingerprint sensor I'm never getting another iPhone.
I purchased the first gen on release day (2007) and carried it my pocket every day without a case until the 5 came out in 2012. I still have it, it still works.
I bought my iPhone 5 in 2013 and carry it my pocket every day without a case. It has some cosmetic damage.
Not fanboy-ing; I think it's legitimately interesting that most smartphones are still designed the way early cell phones were: plastic case around components, clipped or screwed on, flimsy from day one.