Simplified....
More steempower = more voting power.
Voting power = how valuable your upvote is
Steemitboard runs a bot which rewards newcomers with an upvote for accomplishing various milestones
It is aimed at providing something to assist in engagement and reward for minnows.
Due to the rising number of new accounts the bot can't be set to vote with full power or it will run out too quickly
By upvoting steemitboard comments/blog posts you help contribute to the amount of available steem that steemitboard can utilise to continue serving at optimum efficiency
This is such a great and important initiative for us all, thanks for sharing your knowledge of the inner workings of this powerful project.
All for one and one for all! Namaste :)