A 1:3 is possible but less often achieved.
A 1:1 would be good if a trader can be right, say, 99.9% of the time, which is very unlikely.
If target at 1:2 and within 1 or 2 minutes of entry, target is achieved, well and fine. If let's say the target is at 20 pips, and immediately after entry the price:
1)shoots favourably to 10 pips profit, and the stop is moved to breakeven, the position is protected, thus and trader makes fewer losing trades even if he doesn't make a profit from that trade.
2)shoots to 15 pips profit, if the stop is moved to 10 pips profit, the trader has already secured 10 pips profit. Whether or not to move the target higher would be up to him.
On the other hand with a 1:1, assuming a trader can be 99.9% correct in his trades, well and fine, but what if he cannot? If the trader hits the period of the losing streak, his 1:1 profits will be eroded. Let's say 10 losses in a row?
Contrast a 1:2 or a 1:1.5, the 1:2 gains can more or less compensate for the losses if and when the trader does hit the period of the losing streak.