In Pirandello's Six Characters in Search of an Author, how does the line of development of the play promote the progress of the plot?

I would say that the main concern of the play is not the
logical progress of the plot. Six Characters in Search of an Author
seems rather to focus on the fictional nature of the events that are taking
place on stage. if you think about what happens during the play, there is not much of a
plot. Most of the two initial acts, for example, are used to discuss the Father's and
the Stepdaughter's versions of their relationship, with particular reference to the
events in Madame Pace's brothel. A plot is made by a series of events that the audience
assume are real and true. In the case of Pirandello's play, instead, the audience cannot
ultimately reach the conclusion of whose the true reconstruction of events really is and
who is lying. The third act is concerned with the death of the Little Boy. Yet, as the
character dies, the play immediately presents an alternative version of this event as
some of the actors think that the death is simply fictitious. This lack of a definite
plot that tends towards a logical conclusion contributes to heighten the main theme of
the play: the absence of a clear boundary between reality and illusion and the
consequent uncertainty that dominates the human condition.