I have been in dev, qa and support roles. When I write code today, I always keep in mind what steps I can take to help folks in support troubleshoot any issues with it. Having clear and informative logs, comments including wiki links for more details etc. I have a lot of empathy for support now. Once you have to baby sit an error-prone daily batch or deal with issues from users who think you aren't much use - things that basically screw up your day - you never forget.