Update: NOT scammed by smartsteem (only by promobot)

EDIT: Look at their answer in the comments. We're all getting more value than steemit shows us for now. Sorry, @smartsteem!

Is there any reason I would get a negative roi upvote from the @smartsteem bidbot when I was the only bidder for that round and it upvoted for less than 60%?

No, there is not. I'm supposed to get a 20% profitable vote and I get negative roi. I'm just going to hope my experience won't be the same as what @promobot had to offer - scammed me out of my money and didn't even bother with a response.

Investors beware - both of these are malfunctioning. Don't waste your money or delegate to them while their services aren't fixed.