Depending on legacy systems and the software that runs on them is a challenge can be solved with software modernisation. Many companies still rely on legacy systems to run their business, having made huge investments in these. Software modernisation is driven by different business and technological needs and can have many aspects, forms, aims, and benefits.
If your business relies on a legacy application, then you can relate to the challenges of keeping up with innovation. It is difficult to find engineers who have the expertise to provide support for old technologies. The UI might become non-responsive. Or maybe your customers expect more from you as a company.