William the Conqueror: 1061 to 1066

Why you thought this retreat from one fortified camp to another a little further away would be some sort of advantage, we cannot say. It changes nothing, except to confuse and weary your men. Harold continues to build his strength in London until he is in overwhelming force, then he marches down to Pevensey and cuts your men off from the rest of England. His fleet closes in on the bay, cutting your lines of communication. You can stay in camp and starve, or go out and do battle.

The English army is well entrenched by the time you make up your mind: your cavalry charges fail on ditch and pallisade. The battle was hopeless, against a superior foe who knew how to meet your army with proper preparation.