Only when the key is pressed is the I/O active - e.g.for a doorbell. Do not confuse the push button (input mode) on the switch with a push button I/O! The push button on the switch can be used for all modes (on/off, monostable, timer, ...), of which the push button mode (monostable) is one. Never use this type of I/O for long-term contacts on an input module. In that case, I would constantly occupy the bus with the input and thus put more strain on communication.
A push button I/O can not be used on the Cloud. For opening/closing doors, better use a Timer2 (2 seconds).