Why does Allah test us if he already knows whether or not we're going to fail the test?

Bismillahirrahmanirrahim. Peace be upon Prophet Muhammad.

                                                                 Failing? NO!

This is an  interesting explanation we should together think of:

Allaah does not admit people to Paradise or Hell simply because He knows that they deserve that, rather He will admit them to Paradise or Hell on the basis of the deeds that they actually did in this world. If Allaah created mankind and put them in His Hell, they would soon argue that He did not test them or give them the chance to strive. Allaah wanted to refute this argument, so He created them in this world and gave them reason, and revealed His Books, and sent His Messengers; all of that is so that they will have no argument against Allaah on the Day of Resurrection.

Allaah says (interpretation of the meaning):

“Messengers as bearers of good news as well as of warning in order that mankind should have no plea against Allaah after the (coming of) Messengers. And Allaah is Ever All‑Powerful, All‑Wise”

[al-Nisa’ 4:165].

Shaykh Muhammad al-Ameen al-Shanqeeti (may Allaah have mercy on him) said:

In this aayah it clearly states that it is essential to leave no excuse for anyone, by sending the Messengers who give glad tidings of Paradise to those who obey them and give warning of Hell to those who disobey them.

This excuse is completely ruled out here by the sending of the Messengers with glad tidings and warnings, as is stated at the end of Soorah Ta-Ha where Allaah says (interpretation of the meaning): “And if We had destroyed them with a torment before this (i.e. Messenger Muhammad صلى الله عليه وسلم and the Qur’aan), they would surely, have said: ‘Our Lord! If only You had sent us a Messenger, we should certainly have followed Your Ayaat (proofs, evidences, verses, lessons, signs, revelations, etc.), before we were humiliated and disgraced’” [Ta-Ha 20:134].

It is also referred to in Soorah al-Qasas where Allaah says (interpretation of the meaning):

“And if (We had) not (sent you to the people of Makkah) __ in case a calamity should seize them for (the deeds) that their hands have sent forth, they would have said: ‘Our Lord! Why did You not send us a Messenger? We would then have followed Your Ayaat (Verses of the Qur’aan) and would have been among the believers’”

[al-Qasas 28:47]. 

answered by : Ahmad Deedat.

In my opinion,even the Qada' and Qadar is His,Allah keeps the fate of people by Himself. We shouldn't blame our fate and not trying our best in this world simply because of such reason "everything have been  decided by Allah". Allah gives us choice, and at the same time He gives us the attemptability to try. We as a human being shall built the courage in order to get the best, and be wise. That's how we'll create our greater ummah~