Minnowbooster review, my experience for more than a month and no earning

Hi steemians
As new comer I tried lots of services here from other members. like minnowboster
Though the site shows lots of members in there and they say that their VOTING POWER is very high, I found the following.
There are many members in there are not active, I mean they are old members who are not even active in the site or they left the site I mean steemian
second, the voting power ( which is the value that you pay for, so you can have valuable upvote) at first was %60 or so never higher than that now for the last 10 days its never higher than %57, which means you do not get real benefit for what you pay for.

What is going on minnowbooster? can someone improve it? or thats it?