Because most weebs only workout to look like their favorite anime characters and fail to realize that real life people can’t look like most anime characters naturally. Looking even slightly like Guts or Goku would take a lifetime of commitment that a Weeb isn’t prepared for. Most weebs use anime/manga as escapism as is thus slightly to very detached from reality and how basic things like gaining muscles and losing fat works in reality. I have meet dudes online that think they can look like Toji from JJK by just lifting 1 year. It’s easy to get a branded tattoo, it’s harder to count calories and doing cardio.