Here's a thought I had yesterday while doing some day game...
When it comes to pickup, you should focus on efficiency as opposed to trying to do the 100% perfect approach.
Here's why, there are a lot of things that can go wrong in a pickup that you won't find out about until you do the approach.
For example, you can approach as the girl is just about to walk away, you can approach a girl who has a wedding ring on, you can approach a girl who barely speaks English, etc...
So because there are all of these things that can go wrong that you can't realistically predict you want to focus on being as efficient as possible so that if these things come up in the midst of the pickup you haven't wasted time, effort or energy analyzing or waiting for the right time to approach.
Instead it's better to just jump into the approach and be willing to leave it if there's some inherent problem you find after the fact.