there's a difference between "zero-sum" and "zero-expectancy".
zero-sum indicates a finite system. every withdrawal entails an equal deposit. how those withdrawals and deposits are split doesn't matter. the fact is there is a limited pie and when someone takes a piece, someone else goes hungry.
zero-expectancy has more to do with efficiency and probability. it implies that market forces have converged so that at any given moment the current price offers no economic advantage to either the seller or the buyer.
both concepts are fundamental to trading. zero-sum implies that for every winner there is a loser. it also means that while there will likely be some winners, not everyone can be a winner. with trading, if there are a few big winners, it stands to reason that there are many losers.
retail traders enter every trade with a less than zero-expectancy (i.e. negative expectancy) because of slippage (the likelihood of an order being filled at worse than the mid-point of the bid/ask spread) and commissions.
if every option trade is a negative expectancy wager and the net outcome is zero-sum, it also stands to reason that a trader can only win this kind of game through chance ("luck") or skill.
there is no "strategy" that bestows either luck or skill. strategy is mostly a form of trade selection and set of entry signals. but negative expectancy tells us that no matter how simple or complex the entry strategy might be, it is certain to deliver losses if followed over the long run. yet i'd guess 99% of what is sold as market expertise and advice falls under this category.
if purveyors of market expertise were honest, the first thing they'd tell their clients is, "my strategy is as good or bad as any other, if you follow it, you will likely lose money. in fact, since you are paying my for my advice, you are further aggravating your negative expectancy."
whether you are buying or selling an option doesn't matter. in fact you are better off randomly entering any trade. if you enter randomly, you have no bias and will thus react to the market more objectively. the only way i know to develop skill at trading is to make these random trades and somehow, consistently find a way to make them profitable.
zero-sum indicates a finite system. every withdrawal entails an equal deposit. how those withdrawals and deposits are split doesn't matter. the fact is there is a limited pie and when someone takes a piece, someone else goes hungry.
zero-expectancy has more to do with efficiency and probability. it implies that market forces have converged so that at any given moment the current price offers no economic advantage to either the seller or the buyer.
both concepts are fundamental to trading. zero-sum implies that for every winner there is a loser. it also means that while there will likely be some winners, not everyone can be a winner. with trading, if there are a few big winners, it stands to reason that there are many losers.
retail traders enter every trade with a less than zero-expectancy (i.e. negative expectancy) because of slippage (the likelihood of an order being filled at worse than the mid-point of the bid/ask spread) and commissions.
if every option trade is a negative expectancy wager and the net outcome is zero-sum, it also stands to reason that a trader can only win this kind of game through chance ("luck") or skill.
there is no "strategy" that bestows either luck or skill. strategy is mostly a form of trade selection and set of entry signals. but negative expectancy tells us that no matter how simple or complex the entry strategy might be, it is certain to deliver losses if followed over the long run. yet i'd guess 99% of what is sold as market expertise and advice falls under this category.
if purveyors of market expertise were honest, the first thing they'd tell their clients is, "my strategy is as good or bad as any other, if you follow it, you will likely lose money. in fact, since you are paying my for my advice, you are further aggravating your negative expectancy."
whether you are buying or selling an option doesn't matter. in fact you are better off randomly entering any trade. if you enter randomly, you have no bias and will thus react to the market more objectively. the only way i know to develop skill at trading is to make these random trades and somehow, consistently find a way to make them profitable.

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