Lets say you got a date, but you don't really know the place well, you don't know where you can park, you don't have a plan in case you've got to bail - you now have more things to worry about and it'll make you preform worse. Or lets say you're at the bar, and you're talking to girls, but you can't bring them back to your place and you're relying on your friend to get home. Again, you'll have uncertainty and you won't perform well. You're scared to go for it because to do so, you'll have to figure a bunch of other shit out and make it up on the fly.

The plan doesn't have to be elaborate. Just google parking at the place you'll be having your date. Or make backup plans with your friends in case you go home with someone. Just have a plan in case you get lucky and another in case you don't get lucky. Boom, now you don't have to worry about it and you can focus on macking. It can take as little as 5 minutes, but you'd be surprised how few people actually do it.