The line is associated with JC Denton, the augmented protagonist of Deus Ex, the first person role playing game released in 2000. Fans clipped many of Denton's flatly delivered lines and shared them on forums, videos and soundboards because the serious tone clashes with out of context phrases. This nose picking confession became a favourite for that reason, reused as a reaction clip and in edited gameplay. Its popularity has lasted because the joke needs no setup and works in almost any serious scene.
About this sound
JC Denton saying I like to pick my nose from Deus Ex, a deadpan voice line people drop for awkward confessions, gross out jokes and random gaming edits.
A flat, deadpan male voice delivers the line I like to pick my nose with complete seriousness, which is what makes it so funny. The delivery is dry and matter of fact, with no laugh or emphasis, as if JC Denton is reporting a mission detail. That contrast between the tough cyberpunk hero tone and the childish, gross confession turns a throwaway phrase into an instant punchline. Played alone it lands as an awkward pause, and over gameplay or a straight faced character it creates a sudden, silly break in tension.