"[NATO] is an intergovernmental military alliance between 28 European countries and 2 North American countries. [...] NATO constitutes a system of collective security, whereby its independent member states agree to mutual defense in response to an attack by any external party. [...]
Since its founding, the admission of new member states has increased the alliance from the original 12 countries to 30. The most recent member state to be added to NATO was North Macedonia on 27 March 2020. NATO currently recognizes Bosnia and Herzegovina, Georgia, and Ukraine as aspiring members. [...] Members agreed that their aim is to reach or maintain the target defence spending of at least 2% of their GDP by 2024."
Will any state leave NATO by 2024?
The question resolves positively if any state that is a part of NATO at the start of this tournament has left NATO by 2023-12-31. This requires that the state has actually left NATO by that date, rather than merely announcing its intention to leave or beginning the process of leaving.
This will be resolved based on an official statement by NATO, for example by the state no longer being included on the member list on NATO's official website.
If a current NATO member fragments into two or more successor states and none of those successor states are NATO members, that would resolve this question positively. In contrast, if a current NATO member fragments and at least one successor state remains a NATO member but at least one successor state is not a NATO member, that would not count toward a positive resolution.
For simplicity, in the unlikely event that a state leaves NATO by 2024 but then also rejoins by 2024, this question will still resolve positively, since the state had left NATO by 2024.