Whilst I've never been in the conformation ring and seen a judge measure a Rhodesian Ridgeback, I have heard judges say that to hunt lions, Rhodesian Ridgebacks need to be big.  Another thing I hear a lot is the misconception that Rhodesian Ridgebacks are bred to kill lions.  Neither are true of our breed.  Rhodesian Ridgebacks are a protecting breed, and are the only hound to hunt using both sight and scent (think Whippet as a sight hound and Bloodhound as a scent hound).   Rhodesian Ridgebacks were bred to protect and thus keep lions at bay.  (You may hear the term "bay lions", which is exactly what this means).    

Hunting large game requires a Rhodesian Ridgeback to have endurance, agility, speed, a keen prey drive and an overall willingness and ability to work.  Size does not determine any of these disciplines and we must remember that our breed standard states 24-26" from floor to withers (end of neck at shoulder) in bitches and 25-27" from floor to withers in dogs.  

Having watched Rhodesian Ridgebacks on the coursing fields in the USA, and my own dogs playing on the fields of our farm, I know they work in packs.  The larger dogs have one role and the smaller dogs have another. Somehow (seemingly telepathically) within the pack, they work out the individual roles of each pack member.   My smallest pack member is Verde - who stands 24" at the withers, and whilst she's moderate in size, she's mighty in her ability to turn and twist whilst on the run, follow the chase, and her overall agility leaves many in her shadow.  No, Ridgebacks do not need to be big to perform the job they were bred to do.  

Here she is "digging in" during a game with her daddy Colby.  A photo that captures her speed, agility and spirit.  And in my opinion, a dog needs plenty of spirit to bay a lion!