Why was the linkup between the commandos and airborne troops at the Orne waterways important?

The linkup between the commandos and airborne troops at the Orne waterways was a critical objective of the Normandy Invasion because it secured vital exit routes for the seaborne forces landing at Sword Beach.1

Earlier on D-Day, the British 6th Airborne Division had executed a daring glider-borne assault to seize these bridges intact, effectively isolating the battlefield and preventing German reinforcements from reaching the invasion area. By successfully connecting with these airborne units by 1300 hours, the 1st Special Service Brigade—led by Simon Fraser, Lord Lovat—ensured that the left flank of the landing area was secure, allowing the Allied forces to maintain their foothold and continue their advance inland toward Caen.12