There are common reasons why traders fail in forex.
1. Most of the brokers offer high leverage and most of the traders chose high leverage trading.
2. Most of the traders do not wait for the right setup (do not have patience).
3. Most of the traders do not put SL.

and last but not the least, traders start fighting with the market when SL gets hit (If it was put).

Traders should always trade with a proper planning and should accept whatever market offers them. Try to win the market with patience instead of fighting with it aggressively.