When you strike the enemy and overcome him, never give up the pursuit as long as your men have strength to follow ...
  Lieutenant General Thomas 'Stonewall' Jackson

ROMMEL WAS initially unaware that the Allied force holding Cyrenaica had been severely depleted for the defence of Greece. Encounters with Allied forces raised Rommel's suspicions about their strength. Disobeying orders, Rommel followed his intuition and launched a concerted attack against the Allies. His suspicions were confirmed and he orders pursuit of the retreating forces.

As the Allies fell back in disarray, rumour fanned the retreat.  For the Allies, the 'retreat' becomes known as the Benghazi Handicap (or the Tobruk Derby). Four British Generals were captured; one of whom was O'Connor.

In the face of the Axis onslaught, senior British commanders and politicians independently decided to make a stand at Tobruk.