Why no 1930s Town-class batch was clearly the worst

Which variant of the 1930s Town-class light cruisers was the worst?

None was clearly bad; the three batches were successful iterations with modest differences in dimensions, power, and detail.

All three batches of the 1930s Town class were capable cruisers, so choosing a worst group would exaggerate small differences. The Southampton group was shorter and narrower and carried less rated power than later ships, yet included highly successful vessels such as Sheffield. The Gloucester group raised horsepower substantially for only a small official speed increase, suggesting caution when comparing published trial figures. Later batches incorporated accumulated design experience, but incremental improvement does not retroactively make the first batch defective.