Why do we call people to Islam and strive in that, despite the existence of a fixed proportion of those who will enter Paradise and Hellfire, as mentioned in the Hadith, from every thousand?

Summary: The question is asked about the reason for working if everything is predestined. The answer is that Allah has made things depend on their causes. Therefore, work and taking means are a religious and rational obligation. Calling people to Islam is a means for the guidance of those whom Allah has decreed to guide. And whoever abandons work under the pretext of destiny has nullified both religious law and reason. The Prophet (peace be upon him) answered this by saying: "Work, for everyone will be facilitated for that for which he was created," and he recited the words of Allah Almighty: "As for him who gives and is righteous, and believes in the best [reward], We will ease him toward ease." So, it is obligatory for a Muslim to work and call to Allah, believing that guidance is in Allah's hands, but he exerts the commanded means. If people were to abandon work and rely on destiny, the affairs of this world and religion would be corrupted. This is what Allah has ingrained in His servants regarding their worldly and hereafter affairs.