Question originally asked on Musing.io - Click here to see other answers
It's like the difference between Medium/blogspot and Quora. One is a blogging platform, the other is a Q/A knowledge sharing platform. (Yes Steemit and Steem underpin Musing.io)
Musing is much easier to create a quick post and get rewarded for it.
This is just my #2cents you can take it or leave it.