Adding 10,000 rows in a loop
Time to insert a row: 1us
Latency to the server: 1ms
Total time: 10,000 * 1ms + 10,000 * 1us = 10,01 s

Adding 10,000 rows at once
Time to insert a row: 1us
Latency to the server: 1ms
Total time: 1 * 1ms + 10,000 * 1us = 0,011 s