It can be annoying sometimes, especially if your life circumstances are preventing you from updating at that particular point. Whenever people ask me to update stories and I can't do it, it can feel like I'm letting them down. But I'm grateful for the support even when I'm not writing, and I've gotten to the point where I accept that if I can't do it I can't do it, and not get upset about it, because I plan to and come back to it. Most of the time though, it's just encouraging, and I'm grateful that every reader that I have. It's nice to know that your writing s meaningful enough that people miss it. I've taken breaks from this site time and time again, but in the end I always come back to it. In my opinion, nagging is a valuable motivator, as long as you are polite about it, and all of my reviewers most certainly are.
I can't speak for Lisa, but sometimes people take a very long break from things that they love and then come back.