The line comes from Hank Hill, the propane-selling patriarch of King of the Hill, the animated Fox sitcom created by Mike Judge and Greg Daniels that ran from 1997 to 2010. Voiced by Judge, Hank opens countless observations with 'I tell you what,' and the catchphrase followed the show into reruns, YouTube compilations and meme edits. It endures because the deadpan delivery works as a universal setup for dry opinions, much like other short reaction clips such as You What that thrive on instant recognition.