If these trading bots were guaranteed money making machine then there would be no need to sell it. The creators would just use it themselves and make large gains. They know it doesn't work half the time and it is essentially useless in a unpredictable market.
You should consider widening your perception of this world.. There is no guarantee in anything, especially in half evolved, unstable crypto market.! When someone makes any guarantees at all, there is certainly a catch! During birth, even a child isn't guaranteed to survive.