Finn was talking with goob and Shrimpo, when Goob started to stutter a bit since he always had a problem and Finn understood, he started laughing, even the next day when they were on a run Finn saw Goob fail a machine

Goob: "D-D-Damn it.."

Finn: "DUDE YOU SUCK!" (You can be Finn, Shrimpo, Goob or even ur oc)