THE BELIEVER’S FAITH is demonstrated during hardships. He fervently supplicates to His Lord, and does not see any signs of Him answering his pleas, yet his hopes and anticipation do not change, and even if the reasons for disappointment become stronger, he knows that for sure, the True One is more knowledgeable of the wisdom behind every happenstance (in his life).
It may be that what Allah wants from the believer is a display of patience or faith, for indeed He does not send upon him these hardships except that He wants from his heart submission to His will, so that He may see how the patience of His slave is, or He wants from His slave lots and lots of pleading and supplication.
As for those who want their supplications to be answered quickly, and start complaining if there is a delay, then this points towards a weakness in faith. Such a person feels that he has a right to have his supplications answered, and it is as if he is demanding a payment for his acts [of obedience].