Errors identified during this phase are corrected, and books are then printed for classroom use. As teachers and students begin using the textbooks, an occasional error may still be found. If so, publishers incorporate the necessary changes into subsequent printings. Errors are corrected. The process is ongoing and begins as soon as a mistake is discovered, but it does take time.
Publishers correct the error as soon as feasible.
It is important to understand that printing a textbook is not like printing a magazine or a novel. Numerous factors must be considered, such as school calendars, textbook adoption cycles, and the fact that only a handful of printers in the entire United States have the type of presses needed to produce textbooks. Time on these presses must be reserved months in advance. The writing and editing that go into creating a textbook call for precise human judgment, and no automated system can replace that. Every program for checking grammar and spelling would find this sentence completely accurate.