I believe that a writer learns from every story he writes, and when you try different things, you learn different lessons. Working with other writers, as in Hollywood or in a shared world series, will also strengthen your skills, by exposing you to new ways of seeing the work, and different approaches to certain creative challenges.
George R. R. MartinI grew up with four T.V. channels. If you missed a show, you missed it. You gotta wait a week for the next one. I'd mail-order books: take a quarter, get an envelope, send off for it and wait until it arrived. I grew up waiting for things.
George R. R. Martin