The height usually maintained for a shower tap is 110 cm above the shower floor or shower tray. At that height, the tap is easy for the average person to operate. With a thermostatic shower valve, at that height it is easy to read whether the temperature is set correctly. Those who opt for individual components - a shower mixer, hose and shower head - can determine the distance between them as desired.
This can be based on your own height. For a tall person, it is nice to hang the shower head quite high. Especially in combination with a shower bar set, this means that the height of the shower tap should probably be a little higher than for people of average height. Conversely, for those who are not so tall, the shower tap will need to be placed a little lower.