My understanding is that lances would break upon landing on a target, or at the very least they would become embedded in their target. Would knights and other heavy cavalry have to have multiple lances prepared for multiple charges? Would they cycle in and out of the front of a formation? Would they have to go back to a squire who would have another lance ready? Or were lances capable of multiple uses?

Edit: Or were lances only used on the first charge and arming swords used in consecutive charges?