PS3 E3 Flasher

Ok I have a question. Why do I watch videos like #1 where they plug the E3 Flasher into their PC and downgrade it but then I watch a video like #2 where they just plug it in and that's it.

#1: How to Downgrade a PS3 to 3.55 with E3 Flasher (EASY!) HackedTutorials - YouTube

#2: How to install an E3 Flasher on a CECH-20xxA/B PS3 Slim model sk8erlewis - YouTube

Thanks for any help in advanced

P.S can you use USB when downgrading on the E3 Flasher as it has a USB slot.

cant find the video. cant answer u.