Why do I still need a PIN?
Not every retailer accepts contactless payments, so there are still going to be times when you're going to have to make payments by swiping or inserting your card into the terminal, then using your PIN. For example, contactless payments have a maximum limit per transaction in New Zealand, so if your transaction is over the maximum contactless limit, you may be asked to enter your PIN. Note that the cap varies in different countries, and can change.
Currently in New Zealand, the contactless limit is $200.