I picture linux (as well as any new operating system) as being a box with pretty buttons on the outside. After a while, you might get bored with just pressing the buttons and would then want to open the box, fool around with what the buttons are connected to, and maybe even rewire the buttons' functions. If after a while you think you want to get "more" out of the box, then learning to program and getting into the guts would be more fulfilling. Otherwise, if you're happy pressing buttons, then by all means just keep on pressing.
The same was with windows, right? I mean, start->programs->word kept you happy for a time. Then you started registry editing, tweaked your video settings, etc., etc.