Principle 3 - Seek frequent feedback through short-term delivery

Deliver working software frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale

This agile principle refers to the general time horizons taken up in sprints. Depending on the project sprints can take up a longer or shorter time horizon. After each sprint the development team will have developed a working piece of software on which is further built when going to the next sprint. Hence, sprints are iterations to the software development process that continuously improve the product.