The phrase "continue to add value" is correct and usable in written English.
You can use this phrase to describe a situation where a person or entity is doing something to increase the overall value of something over a period of time. For example, "The company has invested in training its employees to ensure they continue to add value to the business."
Indeed the challenge for all libraries is to continue to add value.
"We will continue to add value to the service by integrating Canvas if approved by the BBC Trust and we are following Ofcom's pay TV review with interest.
If we are to adapt and continue to add value to our changing environment, we must also work with others to co-create effective solutions.
But the new management must show that, as a corporate parent, it can continue to add value to the businesses it controls.
Mr. Lombard said that since taking a broader approach in the shops, "we have done nothing but continue to add value to the credibility that we've been able to build around the Starbucks voice".
As it was for ICI, the challenge for any other multibusiness company would be first to identify the ways in which linkages among all or some of its businesses might continue to add value under the appropriate corporate management, then to decide whether it has the ability to provide that management.
Any leader who overstays that better do so with some real confidence that they're continuing to add value to the organization.
Businesses must play to their strengths to innovate and diversify where possible, and identify new opportunities in new markets – all while continuing to add value for their existing customers.
Where librarians see future opportunities for continuing to add value, through for example managing metadata on institutional repositories for content published from their institution, there is an implicit shift in role – this is effectively a publishing function, making content available to be used by a community well beyond the library's own institution.
Evaluate which aspects of the organization are continuing to add value to the business, and strive to improve upon them.
