I just checked and you made a $0.20 vote for your $0.10 investment. This is a 200% return!
It depends on how busy the bidding window is. Usually you make a good profit and when a lot of bids come in you may only break even. This is similar to all the other bots out there. Even if you break even you still likely make out ahead. With more upvotes and $ on your post attracts more readers and voters. You also have a chance to be picked up in our daily Curation Digest that has been really popular. This will bring even more exposure to your post but more importantly to you, likely bringing in more followers.
and what about this last vote ? :/ sadly
I would read my reply above. There is no guarantee it is profitable immediately but most of the time it is, typically 200-300%. But there are other reasons it may still end up profitable even if it isn't immediately after the vote. If you vote at a time when many others are voting this can happen. Or if someone puts a large vote in during s busy window.