For any piece of information, different people will be extracting different knowledge from it – and for different reasons.
Take a newspaper, for example. Some people just look at the front page to see what the main stories of the day are. Others will immediately jump to the back to get the Sports results. Others will look for the weather maps to see if they are going to have a rained-out barbeque this weekend.
Customisation focusses on the end user – what they need to know to make the right decisions.