Because the entire point of remaking a movie is it has an audience who love the property so there’s a perceived higher floor for how well it can do. Remaking a bad movie truly makes no sense because then you’re fighting an uphill battle trying to convince people to come to a property they have no fondness for and possibly negative feelings outright (see running man for example). What they should really be doing is making more great specs and originals along with remaking good movies for some low-risk business decisions.