I'm speechless, I really thought that it did, thanks GigiA base coat is used to anchor the polish to the nail be it natural or enhanced. A base coat should be soft and sticky ... a base coat does not prevent discolouration (myth).
A top coat is used to protect the polish from wear be it natural or enhanced. A top coat should be hard and durable and very shiny.
Polish will last longer on any client if you use them all. Why wouldn't you? The client is paying for a a job that lasts ... we should be giving them that, not 'short cutting' what should be a professional service.