It's why market analysts invariably fail to predict "the next big thing".

I have a rather different view on why market analysts fail...mostly it's because they always ask 'wool-over-the-eyes' questions like "How would you feel if your [cellphone] was (or wasn't!) the smallest/lightest/coolest thing amongst your circle of friends?" rather than straight forward questions like "Would you pay a premium to have very cool, tinier mobile than your freinds?".

The fact that there is a practical limit to the usability of a yet smaller, phone seems lost on them. Have you ever tried, (or better yet, watched someone else) trying to use one of those really tiny mobiles in a noisy environment? I call it the "cool-cell DTs".

Listen, move down, speak, move up, listen, move down, repeat, move up, listen, move down, re-repeat "Could you repeat that?", move up (quickly), listen,.... :)