While this may seem obvious and you may very well already know what ICM is, you are probably still punting off your stack way too frivolously in marginal spots!
Many of our students come from a cash game background (or have some knowledge of GTO) and believe that you should take every marginal spot even if it’s only a slightly +EV play. In tournament poker, this couldn’t be further from the truth!
GTO ranges are simply chip EV ranges, they do not consider future game or ICM which are critical components in tournament play. Your tournament life is EVERYTHING when it comes to succeeding in poker, and typically you should be playing a bit tighter than GTO in tournaments, especially when it comes to the bigger pots, calling all ins and other big hands.
Future game simply means that you are still able to realize equity and find profitable spots, because you still have chips to play with. If you lose your entire stack in a cash game it’s no problem, you can just buy-in again!
In a tournament however, once you’re out.. You’re out! There is no more future game, no more equity to realize, and your buy-in is lost forever. This is why taking future game and ICM into consideration and playing a bit tighter in big spots is vital to achieving long term success in poker tournaments.