switch

Mechanical or electronic device that completes (closes) or breaks (opens) an electrical path (circuit) to route power or data stream from one point to another. See also valve.

Customer lock-in (that is, their cost to switch to another provider) is an important concept in business. If lock-in is low you're less likely to be able to retain the customer, but if lock-in is thought to be high then the initial sale will be more difficult. Where switching costs are high it's easier to get a new customer than to get a customer to switch from another provider. First-mover advantages are especially powerful in markets with high lock-in.
The ability to detect switching costs and predict how they'll change as time passes is an important business skill. Some types of lock-in rise over time (called creeping lock-in), others fall. Here are some examples of each: contractual commitments (falls over time), durable purchases (falls), brand-specific training (rises), information and databases (rises), and loyalty programs (can rise or fall).
For example, as a supplier, switching costs are the key to valuing your installed base. As a buyer, show the seller you understand how you'll be locked in with them, and explain what your switching costs would be from your current vendor, and use these factors to negotiate a better deal.

• Why Didn't Netscape Win the Browser Wars?