Zero retention coffee bean hopper

A method comprising:

• dispensing, by a dispenser, a first portion of a supply of coffee beans from a hopper and into a grinder;
• as the first portion is dispensed into the grinder:
• grinding the first portion by the grinder,
• measuring, by a weight sensor, a total weight of the hopper and a second portion of the supply of coffee beans that is contained by the hopper and receiving, from the weight sensor, data characterizing the total weight, and
• detecting, based on the data characterizing the total weight, a deviation of an operating parameter associated with the hopper, the dispenser, or the weight sensor from a preset value.