Nowadays, many people are losing considerable wealth due to online scams. Phishing is one of the means that a scammer can use to deceitfully obtain the victim's personal identification, bank account information, or any other sensitive data. There are a number of anti-phishing techniques and tools in place, but unfortunately phishing still works. One of the reasons is that phishers usually use human behaviour to design and then utilise a new phishing technique. Therefore, identifying the psychological and sociological factors used by scammers could help us to tackle the very root causes of fraudulent phishing attacks. This paper recognises some of those factors and creates a cause-andeffect diagram to clearly present the categories and factors which make up the root causes of phishing scams. The illustrated diagram is extendable with additional phishing causes.