In order to interact with the blockchain on steem it you burn 'bandwith' this is proportional to the amount of steem power you have and regenerates much like voting power.
Hence no / low SP, interactions are limited, which is not really great for someone looking to engage and broaden their network.
I hope this answers your question.
https://steemd.com/@darkscotty at the top left is your bandwith and voting power.
Thank you @sammosk, appreciated!