Problem with the iPhone 5
...is the infrastructure that many long term iPhone users built up over the years.
I, like many others, have quite the collection of iPhone chargers in strategic places.
Sure, it's just the cables that need to be replaced as the chargers will still work with the new cable, but when cables cost £15 each (or if you prefer, you can get an adapter for £25) then this significantly adds to the cost. Up until now, I've been able to buy a new iPhone knowing that all my previous chargers and cables would work.
I'm not complaining about a change of connector; I think Lightning is a good evolution of the cable, particularly the bit where you can enter it any way up and it works, but it is a cost concern.