In competitions, you play by the rules. If it's stroke play, you hole everything out unless it's a best ball format and you pick up because your partner already has the best score.

For handicap purposes, it's different. If you pick up on a hole you post your "most likely" score that you would have made had you continued play on the hole (but no more than ESC). You don't have to complete holes to post scores. As a matter of fact, you could hit as few as 13 shots on the golf course and post an 18 hole score, but this is an extreme example. I could hit 13 tee shots on 13 different holes, pick up the ball on each hole and score what I most likely would have made on the hole had I continued play. I then score the remaining 5 holes net par. I could post that score. Weird, but true.

Possibly even more strange is that I can not post a score if I play two balls all the way around 18 holes and hole out every putt. I think I should be posting two scores.