What could be the reason for not achieving 9% each month?

One possibility would be that you have set the risk setting too low. Then you make round about 5 % per month. Another cause could be that you have a somewhat smaller, normal account and the compound interest does not yet take effect. Short explanation: The software places the first trade with a lot size of 0.01 / 4.000 €. This means that the lot size is only increased by 0.01 lot every 4.000 €. So, you will make about 250€ until you reach 8.000 €. Now, you earn again round about 8 % (500 €). Another reason could be the market behavior. There are of course many profitable, but also less profitable months.