In most organizations of a certain size, IT budgets are allocated by business units, roughly following the organizational chart. Business units need to present their investment projects which invariably require to purchase, develop or modify some information system component. In many industries, business projects are often quasi exclusively made of IT activities. The investment projects presented do need to show positive business returns when not clearly proven financial returns on investment (ROI).
But very often, the costs and the benefits of a given project are aligned with a corresponding business unit. This impedes the sharing of IT resources across these lines of business. It also hampers the creation of IT assets that could be eventually shared with other units.
Regardless of the benefits they provide, the more IT assets you have, the more you will spend in future change endeavors.
Learn more about how silos of all sorts hamper business agility: https://rmbastien.com/book-summary-the-new-age-of-corporate-it-volume-1/