5. Smithers' Changing Race And Homer's Changing Voice
Due to an initial animation error, Mr. Burns long-suffering, sycophantic lackey Waylon Smithers was shown as black (with blue hair!) in his initial appearance in "Homer's Odyssey", changing to his normal yellow makeup with his next appearance. Voices on the program have changed as well, most notably Homer's initial "Walter Matthau" voice, only present in the very early episodes before voice actor Dan Castellanetta decided to abandon this version as being too difficult to sustain over the marathon length of the recording sessions. The most well-known example of this version of the voice being Homer's quote "Let's all go out for some chocolate frosty milkshakes", said mainly in the Tracy Ullman shorts and The Simpsons 1st season.