I have been the owner of two professional car washes for over 30 years. I have washed well over 1,000,000 cars in that period and talked to many customers, attended to many complaints and praise as well.
Today's customer is broken down into the customer that's in a hurry and only wants a clean car once in awhile, the customer who is not in a hurry and wants a clean car more often and the the "have to customer" - the customer that will come to a professional car wash only because his vehicle is simply too dirty from snow or mud or both. The customer who is in a hurry does not want to spend time in line or outside after the wash (departing the premises) to be towel dried or basically to be on his way - his time line is quite small and will normally want to in and out in in 10 minutes or less. He will not go to a wash with a long line nor particularly one where the lines moves very slowly perhaps in front of an automatic or touchless wash where the wash process is taking 5 minutes or more. If the lines is short and if he is an express wash then he will go in. The customer who is not in a hurry and wants a clean car more often is the bread and butter customer for the car wash owner. He will wait in any line and will wait until his car is properly cleaned. This quite naturally allows the car wash operator to do his best work.
The "have to" customer is neither in a hurry nor is particular about his car. He only wants to have cleaned and be on his way - whether it takes 5 or 20 minutes.
Quality - The above customers all expect a certain quality or value for their money - a clean car. There are different degrees of clean to the customer- what he sees on the surface of his car before he enters the wash, after he leave the wash and at home in driveway or the following day after the vehicle is completely dried - cracks and crevices included. Some owners will spend alot of money insde the wash to enhance the equipment and lighting. Keep in mind that the customer normally does not generally see the nice equipment in its entirely, as he is seeing a lot of soap and movements of machinery. He only wants to ride through comfortably, wants to be sure his vehicle is going safely and the attendants are very friendly. If the car wash owner can provide all three on a consistent basis - then he is doing well. Another important point is cleanliness and organization of the premises. Car wash owners are in the business of clean, so their premises must be clean and tidy at all times. Hoses should never be scattered and twisted on the ground, towels should not be the ground and attendants should give a good appearance. Liken it going into a restaurant - if you were to see dirty silverware, a dirty floor and the waitresses were not very friendly and accomodating then would you go back ? The food may have been very good, but your perception of this establishment is very poor. Conversely, if you were in a restaurant where the food was only marginal but the restaurant was very clean and waitresses very friendly, then which restaurant would you go back to ? Customers go back to establishments are inviting, care for customers and show appreciation for their business.
Let us address complaints in a car wash operation. As indicated above, customers do not know how car washes work and nor do they care. Several times in my 30 years I took customers into the wash to explain how the equipment works. Sure they listen, but do not understand and why should they?
It would be like explaining college level calculus to a 5th grade student. He will shake his head to appear he understands but actually does not have clue as to what you're talking about. The better approach is to listen to the customer - let him speak. Try not to interrupt. The car wash owner, in the end may have to simply pay for the repair if it is only perhaps a wiper or loose molding. In reality the cost to send the customer away satisfied clearly outweighs winning this battle.
There is a lot to be said for damages in the car wash. Normally an owner will indicate to the customer if something on the car has been properly attached, then it would never have come off in the car wash. This is absolute true. Conversely, the customer expects that his car be just as intact after the wash as is was before the wash. It is the wise car wash operator that knows how to handle these situations- low cost and higher cost repairs with his customers. It is often said, a dissatisfied customer will tell 8 people if his experience is bad and only 2 or 3 (at most) if his experience is good.
Keep the customer happy, keep your equipment running properly, use good chemicals, look professional and above all have excellent customer service providing the best overall experience your can in your wash and success will be yours.