I have a materialized view that always does a "COMPLETE_RECOMPUTE", but I can't figure out why.
I found how I can get the logs:

SELECT * FROM event_log(pipeline_id)
WHERE event_type = 'planning_information'
ORDER BY timestamp desc;

And for my table I got this info:

{
  "planning_information": {
    "technique_information": [
      {
        "maintenance_type": "MAINTENANCE_TYPE_GENERIC_AGGREGATE",
        "incrementalization_issues": [
          {
            "issue_type": "PLAN_NOT_INCREMENTALIZABLE",
            "prevent_incrementalization": true,
            "operator_name": "Aggregate",
            "plan_not_incrementalizable_sub_type": "AGGREGATE_NOT_TOP_NODE"
          }
        ]
      },
      {
        "maintenance_type": "MAINTENANCE_TYPE_ROW_BASED",
        "incrementalization_issues": [
          {
            "issue_type": "PLAN_NOT_INCREMENTALIZABLE",
            "prevent_incrementalization": true,
            "operator_name": "Join",
            "join_type": "LEFT_OUTER"
          }
        ]
      },
      {
        "maintenance_type": "MAINTENANCE_TYPE_COMPLETE_RECOMPUTE",
        "is_chosen": true,
        "is_applicable": true,
        "cost": 34936819266
      }
    ],
}

It seems like there is an issue with the left outer join?
But normally that is a supported operation:

https://learn.microsoft.com/en-us/azure/databricks/optimizations/incremental-refresh#enzyme-support