It's rude to go back on a promise.
Ray wakes up with a terrible hangover and has promised to get his friends home early in the morning, so they can make an appointment.
Ray wants to go back to sleep.
Ray hails his friends a ride using a rideshare app before going back to bed.
Ray puts it out of his mind and allows himself to fall back asleep.
Ray's friends end up making it to their appointment on time.
Ray's friends are not able to get back in time and miss the appointment.