Why the Royal Navy moved beyond the Tribal class

If Tribals were useful, why did the Royal Navy not simply keep building them?

Later destroyer programmes tested alternatives; when they did not meet the same role, the Navy returned to the drawing board with the more elaborate Battle class.

The Tribal belongs alongside the L and M classes in the design sequence. Keeping it in production unchanged would have ignored the changing equipment requirement. The Battle class represents a later attempt to combine the desired capability with more weapons and sensors. That additional equipment also made the newer ships slower to build.