Either
you win or lose, one trade is enough to tell yourself, you
have bought it wrongly or bought it at the right time.
This one trade specifies :
a) How much you want to win
b) How long you want to hold
c) How much you want to loss
Asking yourself, why do you have to enter another lot of
trade, if just one could win you the money?
Unless, you have
a) double confirmed
b) saving the first trade
However, if that trade confirms, you would wonder, why not just enter one trade that is confirmed with a more $ per pip, instead of risking the first trade that is not confirmed or look like confirming at the first place.