Machines in gambling eg pokies, and prob most casino games favour the house.
So if payout is 85% (most pokies), you are guaranteed to lose 15% on every play when averaged over time.
A few years back a good mate who is an actuary and who has bet on horses most of his adult life, put together a spreadsheet analysis system that worked on anomolies, scanned all the odds from all the online betting systems, then calculated bets.
Not many using computers for analysis and placing bets back in early 2000's, so odds did not get crashed like today.
Using NT bookies, they would build the bank up to about $30K, then get their account stymied - because they were winning!
Open under another name, up to $30K, stymied, change etc.
They needed my name

, then my wife's name


, for a 25% commission.
"The Bank always needs to win"
Then there was an enquiry into betting in Qld and the anomolies dissipated.
Fun times as I was following the betting on my account as well.
From then on I have only ever bet on the odds and anomolies, sparingly.