It matters. If a price moves certain way it will likely move in that direction for the future but it's not a guarantee. In trading, you just need that edge and money management to bring in profits and not have risk of ruin.
For e.g. in roulette you have red and black and a green zero. Casinos know in the long term they will win, but they cannot predict what color it comes out next. Its not impossible to see 10 reds or 10 blacks in a row.
Likewise in trading, most of the time it looks pretty random and you can have a winning system and still lose 10 in a row. Money management is key during to survive in the rare time when you have 10 straight losers.
