Why admirals often commanded from battleships

Why did admirals such as Cunningham and Somerville often use battleships or cruisers as flagships instead of carriers?

Battleships and cruisers usually had more room for fleet command staffs, while most carriers needed their available space for growing air groups.

Cunningham and Somerville often preferred battleships or cruisers as flagships even when carriers were central to their operations. Those ships normally offered more space for a fleet-level command staff and its communications. Ark Royal had been designed with such accommodation, but later carriers devoted increasing volume to their expanding air groups. Her loss therefore left the Eastern Fleet with carriers that were less suitable as command platforms. An admiral's need for staff space was separate from the carrier's tactical importance.