In some cases, a SIM-locked handset is sold at a substantially lower price than an unlocked one, because the service provider expects income through its service. SIM locks are employed on cheaper (pay-as-you-go) handsets, while discounts on more expensive handsets require a subscription that provides guaranteed income. Unlocked handsets have a higher market value, even more so if they are debranded. Debranding involves reflashing or replacing the firmware to remove the operator logo or any limitations or customisations that have been imposed on the handset by the operator, and is usually accomplished with software designed for a particular handset model, however most smart-phones can be debranded and unlocked solely with use of special software.