With pressure-regulating or dynamometric tampers, a spring mechanism inside the tamper regulates the contact pressure and ensures that you always tame with the same pressure.
Premium models like Hauck's UFO are also self-leveling, so crooked tamping should be a thing of the past.
Pressure-regulating tampers are particularly suitable when several baristas work with one machine/grinder and tamper very differently. The different contact pressures will then be a thing of the past.