spotPlacementScores

The Spot placement score for the top 10 Regions or Availability Zones, scored on a scale from 1 to 10. Each score
 reflects how likely it is that each Region or Availability Zone will succeed at fulfilling the specified target capacity
 at the time of the Spot placement score request. A score of 10 means that your Spot capacity request is highly likely to succeed in that Region or Availability Zone.

If you request a Spot placement score for Regions, a high score assumes that your fleet request will be configured to use all Availability Zones and the capacity-optimized allocation strategy. If you request a Spot placement score for Availability Zones, a high score assumes that your fleet request will be configured to use a single Availability Zone and the capacity-optimized allocation strategy.

Different
 Regions or Availability Zones might return the same score.

The Spot placement score serves as a recommendation only. No score guarantees that your Spot request will be fully or partially fulfilled.