Rocking chair cup holders: mounted or beside the chair?
Compare a chair-specific accessory with a stable side-table setup.

Chair-specific mounts
Check the accessory and chair maker’s instructions. Arm shape, moving joints and finish matter; do not assume a generic clamp fits safely.
A fixed side table
This separates the drink from chair movement. Choose height and placement by actual seated reach and leave clearance for the chair.
A freestanding base on that table
Steadi adds a wider base to compatible drinkware on a supported level surface. It is not an armrest clamp or restraint.
Fit the drink you use
Measure 2–3.15 inches across the container base and check full seating. Low mug handles and added boots can affect fit even when diameter is within range.