Book lovers cringe at the thought of discarding books for any reason. Library science says that it has to happen. That means tension between librarians and readers, who usually are on the same page.

And it means the Charleston County Library has some more work to do to help patrons understand why it is purging the collection, and why a book from the main library on Calhoun Street might be on a shelf at the library on James Island, or a book from the South Windermere branch on a shelf in Mount Pleasant.

The public library is getting rid of 50,000 books that are damaged, outdated or seemingly so unimportant to readers that they don’t circulate at all. Library science standards recommend doing regular purges to allow room for new books and to ensure that the collection is as helpful as possible. Since there has not been such a purge in 15 years, patrons are seeing a dramatic difference in the numbers and titles of books on the shelves. Some regular library visitors are alarmed.

That concern is exacerbated by the other change. It used to be that books, which could be returned to any branch, would end up back at their home sites.

Now they float. They stay where they land. The notion is that they will be where people find it most convenient to look for them.

But what it also can mean is that shelves at the very popular Mount Pleasant library will be full, and some shelf space at the main library will be bare.

Hence the need to help patrons adjust.

Those who have, understandably, come to expect the large main library to be the flagship — the first place to go for most reading needs — will need to understand that more books are being made available at branches close to where the population is growing.

Those who are wont to wander the stacks until they come upon a book on a particular subject or by a particular author will need to rely more on the library’s computerized inventory.

It might not be at the Dart branch on upper King Street, but a patron there can ask and it will be delivered.

And those who view the Charleston County Library’s role as archival will need to be disabused of that idea.

An academic library like the Addleston Library at the College of Charleston keeps some books that are outdated because they represent the thinking of their time. Those are likely to be removed from the public library, whose collection is designed to meet the informational, recreational and cultural reading needs of a wide array of people.

Despite confusion and dissatisfaction with changes, the number of people using the library is growing. And the very fact that people care enough to complain is encouraging.

The library staff should take this transition as an opportunity to connect with patrons, learn what it is they want from their libraries and strengthen their worthy mission.