What ever made Ar-Parazon arm his fleet to conquer the west?
Envy for the elves is a good reason.
The desire to challenge the power of Valars is another one.
The lies of Sauron constitute a good engine.
Maybe the strongest argument is the search for everlasting-life.
All these statements are correct because they are obvious,
and so let us synthesize the whole of them as I've done in the title of this post: happiness,of course.

If we are to move from the original shaping music,happiness
is simple to define as "being in harmony with one's script".

The case of Ar-Parazon, which will be repeated in a quite different form but not in the result by Denethor, is the most representitave of the dramatic nature of human kind's liberty which in the end can bring him to death.

My question this time is this:
what was the part of Ar-Parazon, or to enlarge the debate,
what was the meaning of the existence of Numernor?

If Eru himself had to put his hand in the matter,
I would like to underline that in the battle against Morgoth He did not intervene,
then things were too far off from their course...