What is the point of the promise of houses in heaven for those who do good deeds?

In a Nutshell: There is a hadith that says that whoever performs 12 rakaa in the day and night will have a house built for him in paradise, but the Qur'an states that the residents of paradise will find everything they want there. Is it not contradictory for us to say that doing this or that will get us this or that in paradise when Allah has informed us that we will have it? It is confirmed that certain pious deeds will be rewarded with the construction of houses in paradise for the benefit of their doers.In this connection, Umm Habibah states that she heard Allah's Messafer (radi allahu an) say: "He who performs 12 rakaa in the day and night will have a house built for him in paradise." (reported by Muslim,728) It is not right for a Muslim to oppose such hadiths with others as the word of Allah the Most High: "Those who say, 'Our Lord is Allah,' and stand in the right path, the angels descend upon them: 'Fear not, nor be grieved; but have the glad tidings of the Paradise promised to you; and We are your protectors in the life of this world and in the Hereafter; and therein shall ye have that which your souls desire and that which ye ask for,'" (Qur'an,41:30-31) under the pretext that paradise is already endowed with all that one would desire there and that the one who will be admitted there will have the right to desire as many houses as he wants and that he does not need to make a prayer of 12 rakaa in the day and night. Indeed, Allah the Most High has decreed to reward good deeds as indicated and He has done so only on the basis of perfect wisdom. Therefore, our belief in His wisdom, grace and fairness should prevent us from questioning ourselves in this regard. Allah the Most High says: "He is not questioned about what He does, but they are the ones who will have to give an account [of their deeds." (Quran,21:23) Sheikh al-Islam Ibn Taymiyyah (radi allahu an) said: "The Transcendent is the Creator, Master and King of all things. His creation is based on perfect wisdom and brings a flood of blessings and general and special mercy. He is not questioned about what He does, not only because He has irresistible power but because His knowledge, power and wisdom are perfect." From the Collection of Islamic Legal Advisory Opinions (8/79). Ibn al-Qayyim (radi allahu an) said: "Allah the Transcendent is wise; He does not do anything unnecessarily so without purpose, without aiming at a benefit and wisdom through the act. Better still, all His acts are dictated by perfect wisdom. They also flow from causes that bring them about. His word and that of His Messenger prove this so often that one cannot count the number and circumscribe the frequency of them." From Shifaa al-ghalil, p.190. Among the reasons for the promise of building a house in paradise are the following: Firstly, the fact that a special reward is reserved for certain good deeds further motivates the worshipper and increases his desire to do well.For the promise goes beyond the entry into paradise and adds to it the enjoyment of a special benefit.This motivation can be felt by every believer. Secondly, it may be that the houses in question are different from others to be desired by the believer in paradise. It is in this sense that the ulama comment on the hadith of Uthman ibn Affan in which he says: "I heard the Prophet (peace be upon him) say: "Whoever builds a mosque (Bukayr says: I think he said:) in order to please Allah, He will build him a similar house in Paradise." (Sahih al-Bukhari,450 and Muslim,533) Ibn Rajab (radi allahu an) said: "The quaificative "such" does not refer to a building of equal dimensions but means (Allah knows best) that he will be provided with a huge and well-made but undecorated building. However, the recipient of the heavenly house will enjoy it to the extent that people benefit from the mosque he has built for them here. The house will dominate the neighbouring houses in paradise as its mosque dominates its neighbours here." From Fateh al-Baari, (3/320-321) These houses of paradise are obtained only through the performance of certain deeds, and therefore they are not like the other blessings granted to the believer in paradise by the mere fact that he desires them. Thirdly, it is true that the believer will have what he desires in paradise but we do not know whether he will desire that particular benefit or not. For the desire for this benefit may be withdrawn from his heart so that he is deprived of it. Conclusion It is well known that the people received in paradise do not have the same degree of enjoyment there and that no one will be given the right to ask for a higher degree of enjoyment than what he has received, because otherwise they would all be in the same boat.