You need to look towards the future. If you do not, the new giant express washes and investment groups will take a large part of your business.
Everyone likes shiny new things. It is how the car industry survives and why your wash can be profitable. The drive for shiny new things leads your customers to your wash, or to the new washes around the corner. Your car wash customers are drawn to new and shiny things.
As your wash ages, making it new and shiny takes time, money (cash flow), and manpower. In your business, like all businesses, you are chasing two out of three all the time. We generally have one in abundance compared to the others.