A fusion plant designed to demonstrate electricity production, known as DEMO, is likely to be very different from existing fusion devices and even from ITER. These differences will be found not only in the technology employed but also in physics areas including, but not confined to, the plasma behaviour. Here, some of the areas where DEMO is expected to be different are highlighted and explored. As a result of the differences between DEMO and existing devices, the fusion community needs to develop a new intuition when considering the design and performance of DEMO.