If you are a computer manufacturer, it is pretty easy to make a smartphone that drains it's battery in 3 hours.
Apple have done an amazing job in the last 4 years to achieve what they have: and old friends from Nokia who have done tear downs on the iPhone 4 still think the HW and OS is rubbish.
And that partly was Nokia's problem, and now it's now to late to do anything about the apalling user experience.
The other part of Nokia's problem was that there were about 8 various different flavours of manager for every engineer who was actually doing work, and they could all put their boot in to stop something from happening, but none of them could actually take responsibility to see something through to completion as an entire finished article. Nokia's organisation and structure was interesting to say the least... and particularly not amenable to being able to achieve anything.