In a service industry job that people pay for eg:hairdressing, you have the customer who is paying for a service,but the knock on effect of somebody being late can throw the stylists day out completely,as they are working against the clock all day.so if mrs Jones is 15minutes late for her 10am appointment & u have mrs smith coming in at 10.30 am where do u make up the time, this can lead to people leaving your salon if it becomes a regular thing.
one client that i had got so bad at time keeping she was always 15 to 30 minutes late she was always told 30 minutes earlier than her appointment & therefore was on time.
lateness can put pressure on some as time is money,but when you are in a service industry & they are paying for a service they can go where they want so if somebody is kept waiting all the time it can lose you clients,and reputation.