I do the Goodreads challenge every year, but in a way I wish I didn't. It does put a lot of pressure on me (actually I put the pressure on myself), and keeps me from trying new authors, new genres, and high-page count books. One benefit, however, is that it makes it easier for me to give up on a book I really don't like, which I seem to have a hard time doing.
^^^^what Patricia said. This might be my last year to accept the Goodreads challenge. I think next year my challenge will be to myself to simply read at least one chapter from a book daily. No more, no less. Slow, steady reading through the year. Let the chips fall where they may.
One benefit, however, is that it makes it easier for me to give up on a book I really don't like, which I seem to have a hard time doing.