Bottles are the end product in the chain of producing whisky. You can't change the characteristics of a bottle (e.g. age) anymore. Whisky in cask is like a raw material, where age, quality and scarcity are not yet finalized. The table below shows the differences. 


Bottles

Whisky in cask

End product in the chain of producing whisky

Raw material

Age and quality is determined

Maturing in cask 

Value increase driven by scarcity

Age can be extending the maturation period.

Quality can be improved by re-racking  into other casks.


Scarcity is dependent on the moment of releasing the bottles.