Revolutions per minute is the most oversold number in tennis

Spin gets quoted like a horsepower figure, but the shots that cause damage are defined by where they land and how high they cross.

The rpm figure arrived with tracking systems and immediately became a bragging number. Three thousand. Four thousand. Broadcasts treat it the way motoring writers treat torque, as though the larger figure automatically wins the exchange.

It does not, and the reason is simple. Spin has no value by itself. Its value is that it lets you clear the net by more while still landing the ball deep, and that it makes the bounce awkward once the ball arrives. Both of those effects are downstream. If a player produces enormous spin and the ball lands two metres inside the service line, he has generated a wonderful number and handed over the point.

Net clearance is the reading I would put on the screen instead. It says something about risk that spin cannot. A ball crossing thirty centimetres over the tape is a different decision from one crossing a metre and a half, and choosing between them is the actual tactical content of a rally. Depth is the other one. Depth and clearance together describe a shot almost completely, and they describe it in terms the player can change on the very next ball.

There is also a cost to spin that gets ignored. Heavy topspin bleeds pace. The racket head travels a long way vertically to produce it, and that vertical travel is not going into the ball's forward speed, which means the opponent gets more time. On a slow, high-bouncing surface the trade is worth making, because the bounce does the damage instead. On a low, skidding court it can be a straightforward gift, arriving at a comfortable height with nothing behind it.

The best players adjust this constantly and never talk about it in rpm terms. They talk about heavy, or flat, or through the court. Those words are doing real work. They describe an outcome at the far end rather than a property of the swing.

I would happily see the spin readout retired from broadcast entirely. It flatters the wrong shots. It hands a player a target he can max out on the way to a straight-sets defeat, and there is no worse kind of feedback than that.