Why exactly? If you are a programmer, you need only to have certain notions in how art and game design are made, so you can work better with other people. If you mean to do it all alone, well, you will be able to achieve much less and you won’t be able to focus and become really good in one field. Being a programmer, I’d say for you to download assets to use in your prototypes, and get together with more people in order to produce real quality games.