Why exactly is it so difficult for some to stop using derogatory, ableist, racist, sexist, antisemitic and otherwise bigot language other than that they want to

Why exactly is it so difficult for some to stop using derogatory, ableist, racist, sexist, antisemitic and otherwise bigot language other than that they want to be exactly that? We know the power of habits and we know that if you’re a user of the word “retard” in a derogatory sense, your very first thoughts when seeing an actual mentally challenged person won’t be positive. If you’re not a bigot then stop using bigot language. It’s so easy there is no excuse.