How can I explain to my wife that a touch screen phone can be as reliable as regular push button cell phones?

How can I explain to my wife that a touch screen phone can be as reliable as regular push button cell phones?
I don’t know the specifics, but know that touch screen technology, i.e. my Iphone is as reliable as push button. My wife is convinced that if she were to break down there is a bigger chance of a touch screen not working than a push key cell phone. I looked up reliability and found that an iphone is twice as good projected this year on reliability as Blackberry, not to say AT&T is great because there are issues there. The study I saw just accounted for phone malfunctions. We just signed up for AT&T because I wanted a Mac product. My wife ended up with a Karma which is a nice phone, but was the same price if she’s gotten an iphone $100.00 after 2 year agreement which is some BS because Best Buy had them for free and AT&T wouldn’t price match. To me the only reason to think a push key is better is my lack of technological knowledge to explain that a keypad can go out as easy as a touch screen. Anyone have insight into that one. Thanks.