Thanks Sudip for reading,
There is lot of math involved. So let say a vote a minimum ROI of 0%, That means the roI of the bot can not go to negative. And if the maximum suggested bit showing at 5 SBD and 2 people bid for 5 SBD at the same time, the one which was first will get upvoted and the other one will moved to for the next round and will get upvoted after 2.4 hrs, dont worry your money will not get lost.

The return on bid is praportional.
For example if user A bid for 1 SBD and he will get 1.5 SBD worth of vote.
And if user B bid for 2 SBD and he will get 3 SBD worth of vote
And voting done at the same time for all the bidder in that particular round.
Is that answers your question?