Most of the advice you can read online will tell you to work with a shutter speed that’s short enough to ensure sharpness and remove motion blur. That is unless you’re shooting landscapes in which case you should use a tripod and it’s ok to use longer shutter speeds.
This is the kind of thinking that I believe limits creativity. It’s kind of a black or white thinking with no room in between. After actually spending some time shooting different subjects in various conditions, you’ll come to realize that things are a little bit different.
– PhotographyTalk.com
http://www.photographytalk.com/photography-articles/5349-using-slow-shutter-speed-to-stop-motion