If poker was played straight then there would be no point as the game would be a zero sum game in the sense that everyone would get good cards and bad cards evenly. Just like if you flip coin long enough it will be heads or tails evenly split.
The trick is to turn the even split into a rigged situation. The obvious way is to mark the cards or have another deck of cards in easy reach so that you can get the card to make up your ‘winning hand’.
The other way of rigging the game is to trick your opponents into either believing that you have a weak hand or a strong hand when the opposite is true. This surprisingly is more preferable way than cheating which mark cards, extra cards or even pot theft in which a thief will blatantly steal chips/cash out of the pot. I witness this once in a game I was watching and could not catch my breathe at the sheer audacity the thief exhibit.
When you use the lying and subterfuge tactic to when a game, you are using psychology to get you opponent to do your bidding. It is a form of power play. A bit like politics uses the desire of the population to give up power to elites to do what ever they want.
The only problem with the strategy is when you get discovered lying and then you have a up hill task and recently I have been caught out so much that I feel like a salmon who has a masochistic personality disorder while in a fishing lake.
So you end up trying to double bluff and when that fails you are stuck with having to play straight and that is not the ideal position to be in because you can see others bluffing and double bluffing but you cannot do anything about it just in case you are not in the lead.
When a flim flam merchant gets pied in the face the game is up and you might as well watch football or make a fool of yourself by getting drunk and trying to chat up a non-responsive barmaid.