It's a feature not a bug, who wouldn't want a phone that moulds itself to the shape of your buttock?
On a more serious note though hardware design for something like a phone should expect at least a little rough handling, we all know what users are like. While I wouldn't sit on my phone I can admittedly imagine a situation where I was sat in the window seat of a crowded bus and being squashed up against the window to the point where my phone in my pocket may be pressed against the interior panelling of the bus, though I do tend to keep my phone in a case so this would probably be less of a concern for me personally. When you throw devices out into the real world, especially when it's a device you expect people to carry with them on a fairly regular basis, crap happens. That doesn't even count people who get a bit careless after a drink or two, which while it may arguably be their own fault is something that is known to be fairly common and will result in the user blaming the hardware design.
Like with software people can have some pretty ridiculous expectations of hardware. They expect it to be powerful yet with enough batteries to last a massively long time, they expect it to be compact and light yet they also expect large screen size and near indestructability. Intellectually they may not know they do so but when it comes to real world use if the device fails to meet expectations they'll label it as junk without rational consideration. The designer has to balance these in a way that meets the needs of the userbase in the best way they can, the durability factor of the new iPhone may or may not be an error in this balancing act but time will tell. We may see Apple offering free rudimentary cases in the same way they offered bumpers after the antennagate fiasco if there's enough of a backlash from users and/or the media.
Makes me wonder if this will become known as "bend gate".
cx2
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To live by honour and to honour life, these are our greatest strengths and our best hopes.