InfluxDB purpose of "_field"?

Hello everyone,
I’m using OH3.3 to store my measurements in InfluxDB2 and I was wondering why OH3 fills into the column “_field” always the string “value” for every entry.
Is there a purpose for that? In the documentation of the influxdb persistence it’s not mentioned yet.
Thank you

I think the reason is that OH uses only one field/value pair per measurement. Thus “value” works fine for the single field.

But InfluxDB can have more than one field/value pair per measurement. Imagine that the measurement were “voltages”. Then the field/values could be “incoming”:237, “generator”:222, “battery”:13.8, etc.