Nietzsche discovered that all life desires power and thus all humans want power even if they don't consciously know or even deny it. He supports self actualization as a means to more power.
From thus Spoke Zarathustra:
But that you may understand my word about good and evil: to that end will I say to you my word about Life and the way of all the living.*
The living did I pursue; I followed the greatest and the smallest paths, that I might understand its way.
With a hundredfold mirror I caught its look when its mouth was closed, that its eye might speak to me. And its eye did speak to me.
But wherever I found the living, there too I heard the speech about obedience. All that is living is something that obeys.
And this is the second thing: whoever cannot obey himself will be commanded. That is the way of the living.
But this is the third thing that I heard: that commanding is harder than obeying. And not only because the commander bears the burden of all who obey, and this burden can easily crush him:–
An experiment and a risk appeared to me in all commanding; and always when it commands, the living puts its own self at risk.
Yes, even when it commands itself, there too it must make amends for its commanding. For its own law it must become judge and avenger and sacrificial victim.
But how does this happen! thus I asked myself. What persuades the living so that it obeys and commands, and in commanding still practises obedience?
Now hear my word, you who are wisest! Test in earnest whether I have crept into the very heart of Life, and into the very roots of her heart!
Where I found the living, there I found will to power; and even in the will of one who serves I found a will to be master.
That the weaker should serve the stronger, of this it is persuaded by its will, which would be master over what is weaker still: this pleasure alone it does not gladly forgo.
And just as the smaller yields to what is greater, that it might have pleasure and power over the smallest: so does even the greatest yield, and risks for the sake of power–life itself.
That is the yielding of the greatest, that it is risk and danger, and a dice-playing for death.
And wherever there is sacrifice and service and loving glances: there too is the will to be master. By secret paths the weaker slinks into the fortress and into the very heart of the more powerful–and there steals power.
And this secret did Life herself tell to me.* ‘Behold,’ she said, ‘I am that which must always overcome itself.
‘Indeed, you call it will to procreate or drive for a purpose, for what is higher, farther, more manifold: but all this is one and one secret.
‘I would rather go under than renounce this one thing: and verily, where there is going-under and falling of leaves, behold, there life sacrifices itself–for power!