Lost Cartoon Pilots that STILL Haven't Been Found!

For as popular as some older cartoons have become over the years how is it that their original pilots are still lost?

• #film_animation
• #lost_media
• #lost_media_wiki
• #cartoon_network
• #nickelodeon
• #cartoon_network_lost_media
• #nickelodeon_lost_media
• #lsupersonicq
• #lssq
• #cartoon
• #cartoon_pilot
• #mystery