Procastination. But it's already explained on Wikipedia:
"This episode, along with Just One Bite, was edited for some reason. It was edited for a reason because the part with the live action race car crashing was cut to prevent children from imitating that stunt. It was cut from the part when Spongebob says, "Gee this is harder than I thought" to the part where he hops into his chair saying "I can feel those juices pumping now!". It had nothing to do with Sandy showing off her bra with Patrick beside her, the Jellyfish playing tennis, or anything else. Still, the uncut version can still be seen in "Christmas", which was released on September 30, 2003. On the other hand, the cut version was shown on May 17, 2005 when rerunned on Nickelodeon without surprise. Today, it still airs on Nick and Nicktoons, with the uncut version being "put away somewhere that the public will never see"."