What is the purpose of life? My late father's favorite motto was " Hidup tu mesti seronok!". Now, he was not a religious man, but I think he striked it right there :-
Here is the Quran's reasons - SO THAT YOU MAY BE HAPPY
2:5 It is they who follow the guidance [which comes from their Sustainer; and it is they, they who' shall attain to a happy state!
2:189 THEY WILL ASK thee about the new moons. Say: "They indicate the periods for [various doings of] mankind, including the pilgrimage." However, piety does not consist in your entering houses from the rear, [as it were,] but truly pious is he who is conscious of God. Hence, enter houses through their doors, and remain conscious of God, so that you might attain to a happy state.
3:104 and that there might grow out of you a community [of people] who invite unto all that is good, and enjoin the doing of what is right and forbid the doing of what is wrong: and it is they, they who shall attain to a happy state!
3:130 O YOU who have attained to faith! Do not gorge yourselves on usury, doubling and re-doubling it - but remain conscious of God, so that you might attain to a happy state;
3:200 O you who have attained to faith! Be patient in adversity, and vie in patience with one another, and be ever ready [to do what is right], and remain conscious of God, so that you might attain to a happy state!
5:35 O YOU who have attained to faith! Remain conscious of God, and seek to come closer unto Him, and strive hard in His cause, so that you might attain to a happy state.
5:90 O YOU who have attained to faith! Intoxicants, and games of chance, and idolatrous practices, and the divining of the future are but a loathsome evil of Satan's doing:' shun it, then, so that you might attain to a happy state!
5:100 Say: "There is no comparison between the bad things and the good things, even though very many of the bad things may please thee greatly. Be, then, conscious of God, O you who are endowed with insight, so that you might attain to a happy state!"
6:21 And who could be more wicked than he who attributes his own lying inventions to God or gives the lie to His messages? Verily, such evildoers will never attain to a happy state:
6:135 Say: "O my [unbelieving] people! Do yet all that may be within your power, [while] I, behold, shall labour [in God's way]; and in time you will come to know to whom the future belongs. Verily, never will evildoers attain to a happy state!"
7:8 And true will be the weighing on that Day; and those whose weight [of good deeds] is heavy in the balance -it is they, they who shall attain to a happy state;
7:69 Why, do you deem it strange that a tiding from your Sustainer should have come unto you through a man from among yourselves, so that he might warn you? Do but remember how He made you heirs to Noah's people, and endowed you abundantly with power: remember, then, God's blessings, so that you might attain to a happy state!"
7:157 those who shall follow the [last] Apostle, the unlettered Prophet whom they shall find described in the Torah that is with them, and [later on] in the Gospel: [the Prophet] who will enjoin upon them the doing of what is right and forbid them the doing of what is wrong, and make lawful to them the good things of life and forbid them the bad things, and lift from them their burdens and the shackles that were upon them [aforetime]. Those, therefore, who shall believe in him, and honour him, and succour him, and follow the light that has been bestowed from on high through him-it is they that shall attain to a happy state."
8:45 [Hence,] O you who have attained to faith, when you meet a host in battle, be firm, and remember God often; so that you might attain to a happy state!
9:88 The Apostle, however, and all who share his faith strive hard [in God's cause] with, their possessions and their lives: and it is they whom the most excellent things await [in the life to come], and it is they, they who shall attain to a happy state!
10:17 And who could be more wicked than they who attribute their own lying inventions to God or give the lie to His messages? Verily, those who are lost in sin will never attain to a happy state
10:69 Say: "Verily, they who attribute their own lying inventions to God will never attain to a happy state!"
10:77 Said Moses: "Do you speak thus of the truth after it has been brought to you? Can this be sorcery? But sorcerers can never come to a happy end!"
11:84 AND UNTO [the people of] Madyan [We sent] their brother Shu'ayb. He said: "O my people! Worship God [alone]: you have no deity other than Him; and do not give short measure and weight [in any of your dealings with men]. Behold, I see you [now] in a happy state; but, verily, I dread lest suffering befall you on a Day that will encompass [you with doom]!
11:105 When that Day comes, not a soul will speak. unless it be by His leave; and of those [that are gathered together], some will be wretched and some, happy.
16:116 Hence, do not utter falsehoods by letting your tongues determine [at your own discretion], "This is lawful and that is forbidden", thus attributing your own lying inventions to God: for, behold, they who attribute their own lying inventions to God will never attain to a happy state!
20:2 We did not bestow the Qur'an on thee from on high to make thee unhappy,
20:117 and thereupon We said: "O Adam! Verily, this is a foe unto thee and thy wife: so let him not drive the two of you out of this garden and render thee unhappy.
22:77 O YOU who have attained to faith! Bow down and prostrate yourselves, and worship your Sustainer [alone], and do good, so that you might attain to a happy state!
23:1 TRULY, to a happy state shall attain the believers:
23:102 And they whose weight [of righteousness] is heavy in the balance - it is they, they who will have attained to a happy state;
23:117 Hence, he who invokes, side by side with God, any other deity [- a deity] for whose existence he has no evidence - shall but find his reckoning with his Sustainer: [and,] verily, such deniers of the truth will never attain to a happy state!
24:31 And tell the believing women to lower their gaze and to be mindful of their chastity, and not to display their charms [in public] beyond what may [decently] be apparent thereof;
hence, let them draw their head-coverings over their bosoms. And let them not display [more of] their charms to any but their husbands, or their fathers, or their husbands’ fathers, or their sons, or their husbands’ Sons, or their brothers, or their brothers’ sons, or their sisters’ sons, or their womenfolk, or those whom they rightfully possess, or such male attendants as are beyond all sexual desire, or children that are as yet unaware of women’s nakedness; and let them not swing their legs [in walking] so as to draw attention to their hidden charms And [always], O you believers - all of you - turn unto God in repentance, so that you might attain to a happy state!
24:51 The only response of believers, whenever they are summoned unto God and His Apostle in order that [the divine writ] might judge between them, can be no other than, “We have heard, and we pay heed!”- and it is they, they who shall attain to a happy state:
28:37And Moses replied: “My Sustainer knows best as to who comes with guidance from Him, and to whom the future belongs! Verily, never will evildoers attain to a happy state!”
28:67 But as against this - anyone who repents and attains to faith and does righteous deeds may well [hope to] find himself among those who achieve a happy state [in the life to come].
28:82 And on the morrow, those who but yesterday had longed to be in his place exclaimed: “Alas [for our not having been aware] that it is indeed God [alone] who grants abundant sustenance, or gives it in scant measure, unto whichever He wills of His creatures! Had not God been gracious to us, He might have caused [the earth] to swallow us, too! Alas [for our having forgotten] that those who deny the truth can never attain to a happy state!”
30:15 as for those who attained to faith and did righteous deeds, they shall be made happy in a garden of delight;
30:38 Hence, give his due to the near of kin, as well as to the needy and the wayfarer; this is best for all who seek God’s countenance: for it is they, they that shall attain to a happy state!
31:5 It is they who follow the guidance [that comes to them] from their Sustainer; and it is they, they who shall attain to a happy state!
58:22 Thou canst not find people who [truly] believe in God and the Last Day and [at the same time] love anyone who contends against God and His Apostle - even though they be their fathers, or their sons, or their brothers, or [others of] their kindred. [As for the true believers,] it is they in whose hearts He has inscribed faith, and whom He has strengthened with inspiration from Himself, and whom [in time] He will admit into gardens through which running waters flow, therein to abide. Well-pleased is God with them, and well-pleased are they with Him. They are God’s partisans: oh, verily, it is they, the partisans of God, who shall attain to a happy state!
59:9 And [it shall be offered, too, unto the poor from among] those who, before them, had their abode in this realm and in faith - [those] who love all that come to them in search of refuge, and who harbour in their hearts no grudge for whatever the others may have been given, but rather give them preference over themselves, even though poverty be their own lot: for, such as from their own covetousness are saved - it is they, they that shall attain to a happy state!
62:10 And when the prayer is ended, disperse freely on earth  and seek to obtain [something] of God's bounty; but remember God often, so that you might attain to a happy state!
64:16 (Asad) Remain, then, conscious of God as best you can, and listen [to Him], and pay heed. And spend in charity for the good of your own selves: for, such as from their own covetousness are saved – it is they, they that shall attain to a happy state!
69:21 And so he will find himself in a happy state of life,
101:7 shall find himself in a happy' state of life;