Because magnemite can learn recycle only through move tutor. Relearner can only teach moves learned through leveling and egg moves the pokemon had when it hatched.
The very sad man
my life is over...I've been shiny hunting a beldum and i finally found one.Im pretty sure you can guess what happened after that.I Freaking Lost It!!!!! Gonna give you guys advice,dont use fling on it just throw dem Ultra Balls at that shinies stupid face...after paralying it of course.