Motivations in ThreatActor could be defined better

[rpiazza]

The Threat Actor SDO has two properties: primary_motivation and secondary_motivations. Both are optional. However, there is no normative language about how they relate to each other. For instance, should you have secondary motivations if you don't populate the primary_motivation property?

[jordan2175]

I believe the idea was, you may or may not know the primary reason they are doing what they are doing, but you have intel into a bunch of "secondary" reasons for it. Or the primary reason is classified, and you can only share the secondary. But I do admit that it is a bit weird. But people complained when we had just a list of motivations since they said there needs to be a "primary". I know you know this, I am just putting it here for the record.