Commissions Fees and Spreads !
Many years ago I took a year off work to trade the Dow - Despite winning more bets than I lost - Account went down. Yes I did become profitable after realising why - but not profitable enough to be “better than working”.
When we “record our trades” we only tend to record the actual buy and sell prices we trade at.
instead of this record the buy and sell prices at the buying time and also at the selling time, then work out how much you are paying in spreads or commissions at each transaction - you’ll find you are paying a huge amount of money for the privilage of “playing the game” - then adjust your trading activities accordingly 
You could do worse than study this thread which I posted a while ago !