I do not understand why the price of BTG is getting worse and there is no progress I bought from 0.0195 and now it has fallen by half, can anyone explain

BTG has no future at all thats because. Devs already took their money and all other just loose.
Exactly. What did you expect even from any Bitcoin xxx forks? This is pure marketing designed to trick people based on good bitcoin name and nothing more.
Do you mean BTG has no future

I'm still unsure of your reasons because I'm sure BTG will follow the BCH's stable footsteps and have excellent innovations
BTG used to be in the first ten coins with highest rank in
http://coinmarketcap.com. This site lists the coins together with their market cap (as the name suggests). It is undoubtly just a rule of thumb, but I like to think of that listing as related to popularity of each coin.
And what is happening is that BTG is going steadily down ever since. I have never seen it go up, but every few days it is down one or more places.
Today it has rank #22.
I am not saying the coin has or has not worth or value. I am only saying what I have been observing on the coinmarketcap service since BTG inception: it is going steadily down.