I consider it ad-hoc when the request escapes the planning phase and goes directly in to my pile of work as top/near top priority. A little bit of this is unde

I consider it ad-hoc when the request escapes the planning phase and goes directly in to my pile of work as top/near top priority. A little bit of this is understandable. You can't wait for every task to get put in to the backlog and planned out in sprints or whatever. But if you've ever had a week where 90% of your time goes to everything but planned work well... it's really frustrating. There's often a high cost to context switching for developers. There's been some loose "studies" done that confirm this, and I definitely feel it at a personal level. A "quick request" isn't just the half hour it takes me to do the thing. It's the language switch, the environment switch, forgetting what I was in the middle of, etc, that really causes the bulk of my productivity loss. It gets to the point sometimes where I give two time estimates: one where I'm allowed to shut my door and work, and one where I factor in the likely torrent of interruptions that will more than double my actual completion time.