During open warfare, cease-fires generally do not occur when one side is winning handily. The motive to halt any and all advances is not present. In this case, sometimes they occur on the tactical level to allow the other side to surrender without being wiped out. If a local stalemate has occurred, many are called to help tend to the wounded.
Cease-fires occur when it is apparently in both combatants’ interests. During World War II in the North African desert, an informal cease-fire naturally occurred at dawn and dusk. This allowed both sides to supply the forward units, who would have perished otherwise.
A cease-fire may or may not actually be in both sides’ interests. Sometimes, political interests outweigh the military interests. What the cease-fire allows is for both sides to re-supply and reinforce. Many times, this is in one side’s interest more than the other is. This is particularly true if one side has a dominance in manpower and supply. It is generally not in their best interest because continuance of combat would most likely be favorable to them. In these cases, most cease-fires are agreed to for political reasons.
On other occasions, agreement to a cease-fire is a mistake. It was mistakenly judged to be more favorable to them, but ended up by allowing the opposition to establish themselves more firmly in areas that were not strongly held.
Generally, cease-fires are temporary. The issues being fought over are not decided by cease-fires. In the case where the issue was decided prior to agreement of cease-fire, it does signal the end of the fighting. In this case, the cease-fire is an agreement that the war is over. This is NOT the case in the vast majority of cease-fires. At best, they temporarily stop the fighting to allow both sides to rest and prepare for the next round.