Your question gives away your belief in the Abrahamic worldview where Satan and Jesus are both valid and part of the same Abrahamic mythology and you can "follow" either of them.
In Satanism this worldview and the entire Abrahamic mythology is rejected. Satan is an ancient Pagan god and "Jesus" isn't a real being, he never existed historically. The form of Satanism here is more like Ancient Paganism and Esotericism/Occultism than Judeo-Christian based (there are many Gods, for example) and it doesn't require any "faith" or following a being like you follow Jesus, but knowledge and practice (practices like power meditation and magick are essential here).
As about the "reasons", read the main site (http://www.templeofzeus.org) fully. If you like what you are reading or it clicks for you and you feel a connection, this is reason enough. In Satanism we do not proselytize or seeking to forcefully convert people or scare them into joining unlike Christianity.
Satan tells you to be responsible for your life and actions.
Satan teaches you how to save yourself from real problems in life rather than “sin”.
Satan tells you that you aren’t evil for existing or for not being a robot.
Satan doesn’t threaten you with eternal torture or anything elsr if you don’t follow him.
The thing is one doesn't "follow" Satan. You don't follow your father do you? no. Satan is our spiritual Father so you don't follow him like that. he gives us teachings like any real good father does and those are what we follow and take into our hearts. Yes one can worship Father Satan if one wants to but it's not required in any form beyond the respect demand like one would respect your teacher and father. Father Satan also sees us as his true sons and daughters and treats us as such. He won't leave us weak and empty like these other empty beings. Father Satan's love is true and has proven itself time and time again. Everyone goes thru hardships that is Life plain and simple but he stays by us giving us the tools needed to make Life better. Real tools not empty words. Those of us who have been on this path for a while will tell it to you straight. Take Father Satan's hand and take his teachings into your heart. your life will be better for it.