There can be legitimate uses of insecure work, for example casual work for short term additional assistance, or fixed term work where the work is for a specific project with end date, or when it is to replace an employee on leave such as parental leave.
Too frequently we see insecure work being used for work that is genuinely ongoing in character. There are many reasons for this. Firstly, that insecure forms of work are generally cheaper and do not attract equivalent leave or redundancy entitlements as ongoing work. Secondly, it is far easier to take away the employment of an individual by simply failing to renew their casual or fixed-term contract. Thirdly the workforce is more “flexible” i.e. easier to mould to whatever is the strategic priority of the day. Finally, those whose work is insecure tend to be more compliant and are more easily exploited.