I think for myself, it has been the idea of being able to produce something that is neat or fun. I got into programming originally to challenge myself to overcome goals. I remember my first early sites were based around Pokemon, and trying to mimic the games in a web based format. At that time I learned html and css, but quickly learning perl, then php to be able to make them do more.
They were horrible, but the experience helped me continue to improve and build on them!