Why the Royal Navy accepted fifty cruisers at London

Why did the Royal Navy accept fifty cruisers at the First London Naval Treaty?

Political pressure imposed the settlement, and the First Sea Lord could accept fifty new-build cruisers when he had only forty-eight. Destroyers and modernization of older ships helped compensate.

Political pressure determined the Royal Navy's acceptance of fifty cruisers at the First London Naval Treaty. The First Sea Lord already had only forty-eight, so an allowance framed around fifty new-build ships offered a way to accept the settlement. Large Tribal-class destroyers could help make up the shortfall in capability. Modernizing overage cruisers provided another way to retain useful ships beyond the new construction total.