Ofcourse , Valar loosing the powers as well .
1-Varda Converts large amount of her power to create first the lamps , and after destruction , she made the greatest work by creating the starts , and then she couldn’t create anything else during the darkness of valinor to restore it’s light (except by the help of some maia and all she was able t do is to form courses and loft the sun and moon .
2-Yavana Converts an amount of her power to sow and seeds trees , and after the destruction of lamps she converts a huge efforts of her power to seeds the two trees , and after the death of the two trees she couldn’t create others and she asked Manwe that everyone could do for a single time a greatest thing , which in return can’t do that thing again.
3-Tulkas the one who filled Arda with his laugher and wrath and scattering all darkness before him when he descends , but after spending much much of his power against Melkor and his servants in the war of powers , then when he attacked Ungoliant and Melkor , he got bewildered by her darkness and dismayed and ensnared and was as one caught in a black net at night and stood powerless and his attempts was to no avail infont of her cloud and his wrath was nothing and couldn’t scattered a thing.
4-Orome the great raider and the haunters of beasts , that he spent much of his power hunting and participating in the war of power , but finally against Ungoliant , his throne valaroma faltered and failed , becomes blind, with all his maiar raiders dismayed and lost and becomes blind.
5-Manwe the one with great power save melkor in his prime , his eyes could pierce everything and his might was great and during his fight against Melkor before Tulkas descendant and where he was shaping Arda and after the fight , his vision were decreased and he couldn’t pierce all the darkness in Arda , as well when he couldn’t penetrate the Ungoliant Cloud , Feanor were able to match him and make him perplexed by his response .
6-Mandos the one with harsh heart and Ruthless , but later in time , Lúthien an elf that her singing was able to change his heart and confuse him and got some pity and asking Manwe in this matter and then Eru intervened
7-Melkor , well he turned from the greatest being , to a troll like power where he could be injured by elves.
Atop of that if the Valar has a unlimited power , so how could they became weary and tied of their labor ? and sleeping aswell.
At the end , the Valar and Maiar are like the power of Arda , more and more the time stretched more and more their power fed into Arda itself ,
Varda stored most of her power in Stars , Lamps … , so Varda is the Stars and Stars are Varda
Yavana stored most of her power in some of beings , trees , Ents , … , so Yavana is the Animals and Trees and Animals and trees are Yavana
Manwe stored most of his power as Courage , Wisdom , Sage , Strenght.. ,
Melkor stored most of his power in his Evil creatures and darkness , so Melkor is the Devil and dakness of Arda and Devil and Darkness of Arda is Melkor.