The need for custom golf club fitting can be compared to buying an off the rack suit and having it tailored to fit you. When you purchase your favorite name brand club, before you play with it on the golf course, take it to the range and have it custom fit to you.
I once had a PGA instructor bring me a Scotty Cameron putter he had purchased. He was so proud of his purchase even though he claimed he had not been able to putt well with it and wondered if I could help. After he took 10 strokes, I saw the putter's length was too long for him. I made some other minor adjustments to the club and his putting mechanics. He now consistently breaks 30 putts per round. This is why you can often find me in a golf store like Edwin Watt's, providing customers with custom fittings in a new putter they are about to purchase. Let's face it, perception is everything. If a golfer buys a Scotty Cameron and putts poorly only two conclusions can be made, either its the golfer or the putter. If its someone who putted well before and now can't break 36 putts per round, the conclusion is its the putter not the golfer. Although, golf is certainly a sport you can blame the equipment, it is not fair to the manufacturer if you have not had your clubs custom fit to you.
Belly putters whose purpose is to put the golfer in an upright posture to perform a pure in line stroke must be fit to the golfer. Adjustments to the length, lie or loft angle may need to be made before a golfer can achieve the PILS stroke he or she is looking for. Regardless of the style of putter or the name brand of a putter, all putters should be custom fit to the golfer in order to maximize its intended purpose, make more putts.