Why is malice difficult to prove? i need this ASAP

Although defined within the context of a media defendant, the rule requiring proof of actual malice applies to all defendants including individuals. The standard can make it very difficult to prevail in a defamation case, even when allegations made against a public figure are unfair or are proved to be false. it is a little harder because public figures have more factors to prove. ... Private individuals need only establish that the publisher acted with "negligence." However, where public figures are concerned, the courts have found that there is a lessened interest in protecting the defamed subject's reputation.