Tolerance in machining refers to the deviation from a value between cuts. Therefore, it relates to accuracy, but the value is selected by the client rather than being a feature of the equipment.
Customers that demand that a part's feature be extremely constant from unit to unit will set strict tolerances on that feature to allow for minimal deviation. In actuality, this necessitates more deliberate and deliberate operation of the equipment.
If lower tolerances are set, such as on non-mechanical elements, faster machining can be accomplished.
Although tolerances are defined by the customer, machines typically specify their standard and smallest possible tolerances.