In endgame winning by 10 points can be 99% according to KataGo. And if the temperature of the board is low, with just 1 or 2 point moves available, then you be 15 points ahead and 99.8% winning, pass 3 times and let them grab a couple 1-2 point moves, and then be 10 points ahead and 99.0% winning and get the win awarded to you. So opponent needs to find some big (>15 is plenty, even 10 points could be enough if reduces you to 80% winrate) ko threats you need to answer rather than pass to break your 3 passes strategy. This could happen even with some complex position remaining on the board, which KataGo assumes you will answer correctly, but in reality you are a weak human who might make mistakes so would rather get the win awarded.