If you think about it, how can you lose money consistently when the odds of you losing is only 50%. However, it is true that some traders lose money month after month. In fact, the odds of you losing is higher than 50% since you have to consider the spreads.
You need to ask yourself these questions before you place the trade. This is akin to a war plan and you need to know how you will react when Situation A, B or C happens. Failing to plan is definitely planning to fail. With planning, you will win half the race already.
Another possibility is you do not have a favorable risk reward ratio. If you consistently take profit at less than 1 unit of risk (example: with a stop loss of 50 pips, but you close off your positions with less than 50pips of profit), over time, with a hypothetical win ratio of just 50%, you will still be losing money to the market.
Hence, you really need to trade with a war plan and you need to ensure a sound strategy with a favorable risk reward ratio.