SMS stands for Short message service and as the name tells, texts is best for short message. If you have a lot information you want to rconvey, it may be beneficial to use email or to contact the customer by phone. However, if you want to confirm, for example, that you have received an order, send a reminder of a booked time or notify about a delivery, then this service is perfect. Other examples of things businesses usually communicate via text are discount codes and deviating opening hours.
Use texts when the order is in, the package is outside the door or to communicate a message with multiple people simultaneously.