Everyone's strategy may be the same in one means or another: buy low and sell high. But I don't assume everyone interprets that. And whether everyone's strategy is the same or not, everyone's purpose is to bring about a profit. So let's make a profit in a decent direction. Even if the strategy is not one, if it is profitable, it is nice for one's intellect. And even if it is a profit, what is the fault !!!
The fault that I can think of is that people wants to be the special one and that they don't want other people to have the same strategy as them even though as @kolbalish says, we have some minute difference in strategy, it makes them less superior.
When we are not aware of what are the traders are doing, how we can be different from them?