How do you decide what to put in your garden?

I usually make a decision about what to grow based on what we eat a lot of, what I would like to try, and the expiration date on my seed packets. If something is going to expire this year, we might just wind up eating a lot of it. This doesn't bother me because I can always pass the abundance on to non-gardening friends or trade off with other gardeners who have too much of something else.