The point-count method of assessing the strength of a hand is a good starting point, but there are many factors to consider in determining how “valuable” a hand is. The “value” of a hand, of course, is what it represents in trick-taking potential.
Take the following hand, for example.
If your partner opens the bidding with 1 ♠, showing at least five by agreement, your hand has enormous trick-taking potential. Your partner can draw the opponents' trumps (there are at most three) and still have trumps left to deal with any losers she might have in hearts. This is a very powerful hand to put down as dummy.
It is a common error among new players to count “points” for so-called “distribution” (doubletons, singletons, and voids) in deciding whether to open the bidding. That is a mistake. Shortness has value only when you and your partner determine that you have at least an eight-card fit in some suit. Never count points for shortness as the opening bidder.
Now look at the hand from a different perspective. Suppose you are the dealer. You will open 1 ♠. If the auction develops in such a way that you determine partner is short in your long suit, your hand doesn't look so good, at least not for play in spades. Now, if you find out that partner has a good holding in diamonds, your hand comes back to life — that singleton heart has returned as an asset, and the long spade suit might end up being another source of tricks.
As you can see, the “value” of your hand depends in large measure on what you learn from the bidding. That's why accurate communication between partners is so important.
It is a mistake to assign value to a short suit as the opening bidder, but there is a distributional feature of your hand that can be positive — one or more long suits. Many experts assign extra “points” to a hand for every card in a suit in excess of four.
This hand above is a good example of this principle at work. If you stick strictly to high-card points, it's a 14-point hand. You would open the bidding with 1 ♠ and, assuming partner responded, you would rebid 2 ♠, showing your extra length.
Most experts, however, would look at this hand in a different way. Yes, there are only 14 HCP, but the length and strength of the spade suit argue for a more aggressive assessment. Most would rebid 3 ♠, which normally promises 16–18 HCP. In this case, the upward evaluation of the hand is justified because the spade suit is so good and the side cards are an ace and a king, known in the jargon of bridge as “quick tricks” because you can use them immediately if you need to.
So, take your 14 HCP and add two points for the extra two spades. Now you have 16, enough to justify a jump rebid.