One possible reason for that is uncertainty about the proper shaft length that any given golfer requires in his or her belly putter. Given that belly putters are anchored to the body, and golfers' sizes and shapes differ, an off-the-rack model won't always work. Visiting a clubfitter, or using our belly putter fitting method, are the best bets. Not every golfer has the time or inclination to do that, however.
What if a company created and sold a belly putter whose shaft length was adjustable? That would allow golfers to experiment with different shaft lengths, and also to tweak the length in response to changes in technique, comfort level, or changes in (ahem) the size or shape of the golfer.
Ping Golf has done that with its Nome putter. The Ping Nome was first unveiled in early 2012, in both standard and belly lengths. Now Ping has taken the Nome 405 belly putter and made the shaft length easily adjustable.
Conventional putters most commonly come at up to 36 inches in length. The common range for belly putters is from 41 to 44 inches in length. The adjustable Ping Nome 405 putter allows the golfer to change the shaft length over a 9-inch range, from a shortest length of 37.5 inches to a longest length of 46.5 inches.