There is often a range of several centimeters that can be recomended for any given rider. A rider may prefer a relatively high or low position depending on their body's level of flexibility and the coordination skills they have achieved in their pedal stroke. Both flexibilty and coordination change over time. By experimenting within the recomended range of adjustment a rider can usally find a very useful saddle height position. The ankle and the way each rider positions their foot can sometimes account for differences in saddle height preference.
Some riders pedal flatfooted with the sole of their shoe roughly parallel to the ground.
Some riders pedal with a pronounced tip toe style that is sometimes refered to as ankling. This variable alone can account for several centimeters. The degree of ankling has a pronounced effect on how the muscle groups in the calves are employed. A relatively low saddle position will employ the quads and those ol butt muscles and some of the calf. As a rider's position is raised the muscles seem to work over larger spans.