The Messenger of Allah (sal Allahu alaihi wa sallam) said: "On the night I was taken from Makkah to Jerusalem, Allah imposed fifty obligatory prayers upon my Ummah. So I kept petitioning Him in the matter, asking they be lightened, until He made them but five each day and night." [Sahih Bukhari]
When your best, most beloved friend comes to your house, and you know it is just going to be once in his lifetime, you want to give the best of everything you have to him. If you could, you'd take your heart out and gift that to him too. So when Allah's most beloved, the Messenger of Allah (sal Allahu alaihi wa sallam), came to visit him on the Miraj (journey to the heavens), one of the gifts Allah (subhana wa ta'ala) bestowed upon him was the five daily prayers.
These gifts were not limited to the person of the Prophet (sal Allahu alaihi wa sallam) but extended to all of his Ummah. A parent can't fully enjoy good food or an outing unless his/her children are also benefiting from the same blessings, so the Messenger of Allah (sal Allahu alaihi wa sallam) was given gifts which his Ummah could share in with him.
The prayer is each person's direct connection with Allah (subhana wa ta'ala) – no need for intermediaries. Allah (subhana wa ta'ala) has allowed each of us to present ourselves personally before Him five times every day and ask for whatever we want. If nothing else, unburden ourselves before the Most Merciful, and return to life calm and at peace.
The prayer is obligatory upon Muslims who have reached puberty, are sane, and in purity (please refer to our Fiqh section for more information).
Obligatory deeds are highly rewarded by Allah (subhana wa ta'ala) and performing them is more beneficial than performing any other deed.
Although the prayers were reduced to five, they are rewarded as much as fifty.
Where else can you find the example of such a profitable scheme?