tournaments
ICM pressure
Also: ICM suicide, ICM bubble factor
The tournament effect where medium stacks must fold hands that would be profitable in chip terms, because busting costs them far more real money than the chips they could win. Big stacks exploit it by shoving relentlessly.
Example. On the final-table bubble the chip leader open-shoves 40% of hands because the two medium stacks can only call with premiums.
ICM (the Independent Chip Model) values chips by their share of the prize pool, and that value is not linear: the chips you could lose are worth more than the chips you could win. Near the bubble and at final tables with big pay jumps, a covering stack can attack the players who cannot afford to call. 'ICM suicide' is calling off your tournament in a spot where a fold was clearly right by ICM.