Why do insiders attack? Usually it will be for financial gain. Either someone is offering money for certain information, or they believe they can sell it online. Sometimes the motive will be revenge for a slight against them. It may be in retaliation for receiving a warning or disciplinary action or poor performance review, being passed up for a promotion or project, disagreements around salaries of bonuses, or being laid off. Sometimes it will be for a career benefit, for example taking contact details for customers or valuable intellectual property (IP) to a new employer.