At the other end of the scale , you go right down to the commodity product and the same argument prevails for slightly differnt reasons. If what you are interesting in is a very basic writing instrument to make a mark on paper you have two choices: Do you want to be able to make that mark and subsequently to change it, in which case you go predomnantly for a wood-case pencil, or , do you want to be able to make it and have a certain amount of longevity associated with it, in which case you go for a ballpoint pen ?