I frequently get asked the question: "How many points do I need?" This is especially true when someone wants to overcall, but sadly the answer is not - necessarily - about points. It is also about distribution or "shape". It can also be about where your points are. Take a look at this hand:
A perfectly decent opening bid of 1NT. But if your Right Hand Opponent (RHO) opens anything you cannot bid. You cannot bid 1NT over a suit as you need 15 - 17 to do so; plus you have no 5 card suit to get into the auction with. Nor should you bid if they open 1NT themselves. So now you must - reluctantly - PASS. On the other hand you might have fewer points BUT in a more shapely hand:
I suppose some people might overcall with this hand - good luck to them! Swap the points round, though, and things change radically:
Now you should bid, even though you have fewer total points than the 13 count above. What you lack in HCP is more than compensated by the "shape". When your RHO opens 1C or 1D you can make a weak jump overcall of 2H! And even if they open 1S or 1NT you are still entitled to bid 2H. You might steal the auction and you also give partner a good indication of what to lead if you subsequently lose the auction.
Remember - Points are good but Shape is better. SB4P
This is why there are so many conventional overcalls to show specific shapes before showing the point count.
Shape. If you got it - flaunt it baby...