This is such an important point but people just don't seem to grasp it.
The idea that you have to be the most dazzling job cantidate or the most amazing romantic partner to succeed in these areas probably holds people back a lot. In my experience if you don't do anything overtly stupid, the other party will subconsciously fill in the blanks so that you match "what they were looking for".
That's something you can always suss out (the wise dater/interviewer will always say they do, but subtle cues can clue you into the veracity of that claim).
Regardless, it's still like a sport - if you don't make unforced errors, you will be more likely to succeed.
Consequently practice does help. You're better at dating if you go on more dates. You're better at interviewing if you get more interviews. Practice allows you to "not make silly mistakes" unconsciously, which frees up your more creative side to show the best you.
The idea that you have to be the most dazzling job cantidate or the most amazing romantic partner to succeed in these areas probably holds people back a lot. In my experience if you don't do anything overtly stupid, the other party will subconsciously fill in the blanks so that you match "what they were looking for".