(I dunno... I thought Communicators were pretty durable myself, especially the E90! But everyone treats things differently and I haven't used Communicators in the long term.)

Design and reliability are two separate things which may or may not be related.

As I said in another thread, the test facility tests the design to death, but they don't test all the millions of devices that are actually manufactured.

If a factory doesn't stick to the design specs 100% then problems may come up that are nothing to do with the design, for example if sub-standard components are used then stuff may fail more often than it should. (That's what happened to the very first batch of 5800s, and Nokia was forced to change earpiece suppliers.)

So you'd have to look at two things with a device's reliability: is the device's design reliable, and is the mass production factory reliable?

That would explain why devices are more reliable from some factories than others, because some factories may be sticking more closely to the official design than others. I think a lot of people on here have said that tablets made in some countries seem to be more reliable than the same tablets made in other countries.