Why is insurance a need rather than a want?

It’ll be ok!

It won’t happen to me!

I’ve never needed to claim before!

It costs money!

Someone will look after me!

The Simple English Wikipedia describes Insurance as “… a term in law and economics. It is something people buy to protect themselves from losing money. People who buy insurance pay a “premium” (often paid every month) and promise a duty of care”

There are so many different kinds of insurance, how many do I need, do I need them all?