If the machine is used domestically only, it is ok to have manual shut off (on/off button). However, if the machine is used by guests or visitors, or if it is standing in a public place, it should be equipped with an automatic shut off function. If not, there is a risk that temporary guests will forget to push the off-button, a problem you will not face with an automatic shut off function. All our models come with an automatic shut off function, except Comfort Clean and Easy Comfort that have manual shut off (on/off button).