The Increment must be Done by the end of each Sprint. This means that it should be in a usable condition and meet the Scrum Team’s Definition of Done. The Definition of Done includes criteria that ensure the work is fully usable and meets pre-agreed quality levels.
Although the end of the Sprint is the latest time by which the Increment should be Done, it is considered good practice to aim for completion earlier. Achieving Done status earlier and more frequently helps to reduce risks and enhances the team’s agility.