Allah Ta’ala is Musabbibul Asbaab (The True and Actual Cause of all events).
During the khilaafat of Hadhrat Umar (Radhiyallahu anhu), a Christian clerk was employed by Hadhrat Abu Musaa Ash’ari (Radhiyallahu anhu). When Hadhrat Umar (Radhiyallahu anhu) instructed him to dismiss the clerk, he (Hadhrat Abu Musa) explained that the clerk was an expert accountant. Hadhrat Umar (Radhiyallahu anhu) said that if the clerk dies then some arrangement will have to be made to replace him. Therefore, the same arrangement should be made now (i.e. on the dismissal of the clerk).
When Hadhrat Abu Musa Ash’ari (Radhiyallahu anhu) returned, he found the clerk had died. Hadhrat Umar’s focus was on Allah Ta’ala. Similarly, when he dismissed Hadhrat Khaalid Bin Walid (Radhiyallahu anhu) and appointed the weak Hadhrat Abu Ubaidah (Radhiyallahu anhu) as the governor there was considerable surprise. Hadhrat Umar (Radhiyallahu anhu) mentioned that the focus of the people was on Hadhrat Khaalid (Radhiyallahu anhu). The battle victories were attributed to him. The focus had shifted from Musabbibul Asbaab. Now that a weak man was appointed, the focus returned to Allah Ta’ala.
When there were no reservoirs and dams, the focus was only on Allah Ta’ala. When dua was made, the rains would arrive. Now that people have become reliant on dams, the gaze has shifted from Allah a’ala. The rains too have decreased.

Malfoothaat Part 5 OF HADHRAT MAULANA ASHRAF ALI THAANWI (Rahmatullah Alayh)