It looks like you skipped over the part, "that doesn't rely primarily on luck".
It doesn't depend primarily on luck. It depends on your ability to select a sequence of investments that will have an average payout of more than twice what they cost. You don't know the outcome of any one investment (success or failure), but your ability to pick a sequence of investments that are expected to offset each other's random risks and have sufficient average payout when taken together (expected total gain minus loss averaged more than twice cost), is one of skill, and it relies on decision making abilities.
Good luck is when the average payout turns out to be twice as much as expected and happens less than 1% of the time.
Bad luck is when the payout is half or less, and happens less than 1% of the time.
This is assuming a skilled selection.
When we say "high risk"; we do not mean visiting a casino and placing bets,
where you have an expected loss of 10% due to the house edge, (assuming you had infinite cash and placed bets forever).