Belief in the Preserved Tablet and the Pen includes affirming that no event escapes Allah's knowledge and decree. What reaches a person and what does not were already within divine knowledge.
Belief in decree fosters patience in adversity, gratitude for blessings, avoidance of pride, and reliance upon Allah while taking the appropriate means. Reliance is not inactivity.
One must avoid claiming exhaustive access to the hidden secret of decree, asserting certainty where none was revealed, or turning limited understanding into an objection against the divine command.