User blog comment:Somethingmorethan/Useless SpongeBob facts/@comment-4975464-20141009025837

Forget where I heard this from, but...

SpongeBob was originally supposed to have one hole for every year that he was old. However, considering that this would conflict with the continuity of the show itself, and since the animation for SpongeBob's body would have to be significantly larger in order to accommodate the extra holes, it has since become a lost idea.