Suffering can also be a test and trial for some people. Almighty Allah allows some people to suffer in order to test their patience and steadfastness. Even Allah’s Prophets and Messengers were made to suffer for this reason.
It is important to understand that Allah has knowledge over all things. Allah knows what will happen to us before we do. Allah knows the outcome of all of our decisions.
The true belief predestination in Islam is to believe in the Eternal and Inclusive Knowledge of Allah for everything espoused with the belief of freewill of human-being.
We have not seen anybody leaving his worldly benefits because of relying on Predestination, while some people abandon the means of guidance out of relying on the destiny and fate.