Why is it necessary to keep the button pressed once inside the lift? Isn't there any other system for operating the car lift?

The safety regulations of the 2006-42-EC Machinery Directive, for safety reasons, require that the user, when on the platform, holds down the button for the entire duration of the lift's journey when carrying people if the compartment is not completely enclosed, i.e. without cabin doors. Lifting platforms for people also fall under the same regulation and are operated with a dead-switch command when they have no cabin doors.

From the outside of the platform, the car lift movement can be automatic, by pressing the button once.

For platforms with railings (or positioned in fully enclosed compartments) it is possible
to call the lift from outside by pressing the button only once from the floor panel or by using the remote control.