Some choices countries have made, and guesses at why they chose that way:
1. Scheduling. The event scheduled closest to the team event is likely to have the #2 team member/pair skate, especially in the FS (2018 Russian Ladies), especially if the top two are nearly equal.
2. Perceived inconsistency. One skater may be known as a sp specialist, another as a better at the fs (US 2014 Men's)
3. The top skater may simply choose not to skate one or both events (Hanyu? 2018)
4. The top skater is so much better than the second skater, he/she naturally skates both events ( Kostner 2018) (Davis/White dance 2014)( Chan 2018)
5. Only one entrant from the country qualified (Castelli/Shnapir pairs 2014)
6. Only two disciplines can be split between 2 of a team's skater's
In 2018, for example
https://en.m.wikipedia.org/wiki/Figure_skating_at_the_2018_Winter_Olympics_–_Team_event
The FS is only competed by the Top teams in the SP. For the men in 2018:
Patrick Chan (CAN) skated both SP and FS
Mattie Rizzo (ITA) skated both
Mikhail Kolyada (RUS) skated both
The US split between Chen & Rippon
Japan split between Uno & Tanaka
Chen is overwhelmingly more likely to score high than any other US man, so if he is willing, I hope he skates both team events..
1. Scheduling. The event scheduled closest to the team event is likely to have the #2 team member/pair skate, especially in the FS (2018 Russian Ladies), especially if the top two are nearly equal.
2. Perceived inconsistency. One skater may be known as a sp specialist, another as a better at the fs (US 2014 Men's)
3. The top skater may simply choose not to skate one or both events (Hanyu? 2018)
4. The top skater is so much better than the second skater, he/she naturally skates both events ( Kostner 2018) (Davis/White dance 2014)( Chan 2018)
5. Only one entrant from the country qualified (Castelli/Shnapir pairs 2014)
6. Only two disciplines can be split between 2 of a team's skater's
In 2018, for example
https://en.m.wikipedia.org/wiki/Figure_skating_at_the_2018_Winter_Olympics_–_Team_event
The FS is only competed by the Top teams in the SP. For the men in 2018:
Patrick Chan (CAN) skated both SP and FS
Mattie Rizzo (ITA) skated both
Mikhail Kolyada (RUS) skated both
The US split between Chen & Rippon
Japan split between Uno & Tanaka
Chen is overwhelmingly more likely to score high than any other US man, so if he is willing, I hope he skates both team events..