Why is using the sleep function in PHP to pause execution for a set time not recommended for this scenario?

Using the sleep function in PHP to pause execution for a set time is not recommended because it halts the entire script, causing delays in other processes. Instead, a better approach is to use asynchronous programming techniques such as promises or callbacks to achieve non-blocking behavior.

// Using usleep function to pause execution for a set time without blocking the entire script
usleep(500000); // 0.5 seconds delay
echo "Execution continues after delay";