dumb question from a newbie about hand rankings

I did a search and I haven't really seen this addressed-perhaps someone would assist/link/answer

it has been my understanding that the hand rankings in poker were/are determined by their relative scarcity- the rare the hand-the higher it's ranking-is this correct?

if so, maybe someone could explain to me how and why four of a kind is not the highest ranked hand, rather than the commonly accepted and agreed upon straight flush-with the royal being the highest-

there are 10 straight flushes per suit-using the ace for both high and low-yet there are only thirteen quads-
even allowing for the royals(4) that still leaves 36 straight flushes as compared to the 13 quads-making
the four of a kind much rarer by a factor of almost 3x.

how did the hand rankings come to be agreed upon, and more importantly, why so?

[mrmazoo]

For each rank, there are 48 ways you can make quads, for a total of 48 x 13 ranks = 624.

Remember, JJJJ2h is not the same as JJJJ2c or JJJJ7d.

You can't get all of those straight flushes in one hand. You can only get two per suit for a total of 8. Whereas it's possible to get 13 four of a kind per hand.

[UATrewqaz]

The harder it is to make a hand the better it is

I believe at some point in time straights beat flushes until it was show with math that straights are actually easier to make.

I haven't done the math myself but I believe that the straight is easier to get because you're more likely to get a draw early in the hand.

Let's say your first card is an 8. There are 32 cards that can still help your straight (4 each 9 thru Q, 4 each 4 thru 7). However, if your first card is a diamond only 12 can help.

But once you get to the last card and you have a four flush, 9 cards can help, whereas with an open-ended straight only 8 help. For a close-ended or gut shot only 4 help.

of course I didn't consider the other cards-a very important factor- thanks mr. mazoo for explaining quickly and concisely.

[Cooker]

[ QUOTE ]
The harder it is to make a hand the better it is

I believe at some point in time straights beat flushes until it was show with math that straights are actually easier to make.

[/ QUOTE ]

This is not quite true. It is true that the broad catagories are correct, but often there are problems within the catagories. For instance, it is obvious that there are more A-high flushes than T-high flushes. Similarly there are many more A-high high card hands than there are 7-high high card hands.

[GMan42]

Another wrinkle in this whole thing (I love useless theoretical discussions like this) is that the rankings' relative scarcity change a lot based on how many cards are dealt. In a 7-card game like 7CS or Hold'em, straights and flushes move much closer together in frequency compared to a 5-card game, and if I'm not mistaken, one pair hands are actually more common than high-card hands (although changing hand rankings to reflect this would be silly). If you dealt a game where each player had 10 cards, it would be extremely difficult not to make a straight or a flush, and high-card hands become even rarer than 4 of a kind.

[eisanm]

Your math on the probabilities is wrong, it's more complicated than that.

Either way, the hand rankings were agreed upon based on the probability of being dealt one of those hands in a five card game and they have not been adjusted since, so it is possible they are "incorrect" from a probabilistic point of view in Hold'em of 7card stud for example. Not to mention Omaha.

For the math about quads vs straight flush, a quads is easier to make and this is partly because it only requires 4 specific cards whereas the straight flush requires 5 specific cards, this has been mentioned above in an example with JJJJ7d and JJJJKh (I don't remember the exact cards) .
I have a book which tells a bit about the history of poker but not much about the math. I could probably calculate this more precisely but I won't spend the time.

[AaronBrown]

This is an important early principle in Poker. Most card games have arbitrary and complex rules for ranking. Before widespread literacy, that meant you needed some central authority to set the rules. In England, for example, the Queen's Porter had the right to set rules of card games and could fine people for playing games differently (and could take bribes to cheat players).

One of the things that made Poker an American game, which early players were very proud of, is that it required no central authority. By making the hand rankings based on frequency, the game could not be manipulated as easily by house rules. That's why suits don't matter in Poker, because there's no natural way to rank them. When people did introduce house rules (including straights and flushes) it was important to post the rules in writing in plain sight.

Types of hands are ranked with the less frequent higher, within types the more frequent the higher.