I never want to stand still. Keep moving. Allow for nothing to stop your goals.
These are words to rely on. The future of publishing is not digital and e-books, but print.
People like holding physical books in their hands. The tangible feeling is something everyone wants. In fact, studies show children are not as accepting of e-books than physical books. They read more when holding real products in their hands.
Remember that, when next you publish only an e-book.